So, here's the diary of the whole progress. Typing it will take some time, I hope at least someone will read it

[b:2297hy4t]Some history[/b:2297hy4t]
So what is a C2? What a Z2 is compared to a Z1. Two pickups of the same kind positioned near the bridge and close to each other. To accomplish that you'd just need to route the body, reposition the neck pickup and cover it with a custom pickguard. Hopefully it wouldn't sound too bad.
BEFORE:
[img:2297hy4t]https://lh3.googleusercontent.com/_ycCeFTJWlq8/TcO3Ot4RyMI/AAAAAAAAAg4/sRJr2rfv4Xg/s400/IMAG0022.jpg[/img:2297hy4t]
AFTER:
[img:2297hy4t]https://lh6.googleusercontent.com/_ycCeFTJWlq8/Tc2TfLZMR_I/AAAAAAAAAjE/EJrrt47UZGg/s400/IMAG0050.jpg[/img:2297hy4t]
The idea of the mod is not that recent. I got the idea of the mod before the regular Combustions came out - hacking a bass that didn't even exist. The first mockups can be seen on [url=https://lh3.googleusercontent.com/_6SmzUWkUeMA/Se37i_xeZnI/AAAAAAAAALY/VKMKNZUubOI/s800/combustion_bk_bp_pg_fullshot_esize_133%20z2%20pups.png:2297hy4t]these[/url:2297hy4t] [url=https://lh6.googleusercontent.com/_6SmzUWkUeMA/SsHlDweVFxI/AAAAAAAAATs/7GxN2HV4eVI/s800/jj%20render%20mm%20config%20black%20pg.png:2297hy4t]three[/url:2297hy4t] [url=https://lh6.googleusercontent.com/_6SmzUWkUeMA/SsHlD7G9W5I/AAAAAAAAATw/h4-NbkhkxUE/s800/jj%20render%20mm%20config%20bpearl%20pg.png:2297hy4t]pics[/url:2297hy4t].
Why did I get the idea? Basically, I love the sound of Musicman basses, while I like everything about Dingwalls. The Dingwall-meets-EBMM was my ideal bass. The Z2 basses were just out of my price range. Later I've even created a virtual mockup of such a mix which you can see [url=https://picasaweb.google.com/bocic.ivan/SuperSR5?feat=directlink:2297hy4t]in this album[/url:2297hy4t] (not directly related to the C2 mod, but is trying to accomplish the same thing).
[b:2297hy4t]Decision[/b:2297hy4t]
I've had a fretless AB-II for a year or two now, and as great as that bass is, sometimes that harsh fretted sound is what I need. A fretless played fingerstyle is not the best idea for a punk band. Note that my AB-II is a miraculous bass, I've recorded a punk album with it and it grinds quite well, it's certainly one of the most versatile things around.
The idea is to invest in a fretted bass that will do everything the fretless doesn't: that's power, aggressiveness, roaring, grinding and all the other nasty sounding adjectives without any particular meaning. My fretless can do everything else superbly and will continue doing it, I have no trouble with it; but if I could create a bass that can cover only that narrow space of sounds, and cover it well, I would be complete.
So why the mod? Losing versatility for the sake of more focus at what I need. Also, an experiment is always fun, and I'd end up with something unique and personal. And, if I liked the C with stock pickups before the mod, I could only replace them with Neo FD-3s to add some aggressiveness and be done with it.
[b:2297hy4t]Planning[/b:2297hy4t]
The first thing I did was contacting Sheldon. If anyone knew of possible pitfalls, things I haven't thought through or anything else, he's the guy to ask. After his advice, I created this mockup to see the relative position of the C2 pickups with a Stingray's:
[img:2297hy4t]https://lh4.googleusercontent.com/_ycCeFTJWlq8/TdBh1R9u_WI/AAAAAAAAAlE/yoY6t4TQn3M/s800/black%20c2%20measurement.png[/img:2297hy4t]
As you can see, the positions are surprisingly close. If the actual pickups were on the inside halves of the pickup shells it would be almost perfect. However, that was not doable.
As for the pickguard, some creative thinking had to be done. Using a regular Combustion pickguard is obviously not possible as the route of the old neck pickup would still be visible. In the end, I decided to buy some pickguard material from Stewmac and create a pickguard myself using a hand jigsaw and sandpaper. How would I create the bevel or drill for screw holes, I had no idea, but it's the best idea I had. Then Sheldon offered to create me a one-off pickguard without the neck pickup route that I'd only have to modify to add the new pickup hole.
I couldn't believe what I was reading

I mean, wow. Who knows how would it turn out with my unskilled hands. It was, like, BAM! Sheldon came and saved the day. I was grinning like an idiot for hours after, at once the project became quite feasible, the plan finally came together! Once again, great thanks Sheldon, and I can't stress how grateful I am.
So I ordered two series wired FD-3 pickups in Combustion shells and two black/white/black pickguards with no neck pickup route. Why two? Just in case I make a mistake with one of them. Why black/white/black? B/W/B looks very sexy on EBMM basses, and it has been offered by Stewmac so I mentioned the color to Sheldon when laying out my plan; he offered to create pickguards in the same pattern.
The bass arrived here about a week before the parts.
[img:2297hy4t]https://lh3.googleusercontent.com/_ycCeFTJWlq8/TcO3PFb34rI/AAAAAAAAAg8/1p6_RJ8ivmM/s400/IMAG0021.jpg[/img:2297hy4t]
I've played it a lot before the parts came. The Combustion is great but I didn't really like the neck pickup. To be frank, I couldn't have; my AB-II has a series/parallel switch for the neck pickup, and in series mode it just kills. The parallel wired FD-3a had no chance of impressing me. I decided to go on with the mod, so even if I don't like the new neck pickup it wouldn't be worse then the old config.
Then the package came! Holy mother of all packaging, just taking all the stuff out took half an hour.
[img:2297hy4t]https://lh5.googleusercontent.com/_ycCeFTJWlq8/Tc2R4I-bxdI/AAAAAAAAAiE/iv9oSi7ezCk/s400/IMAG0028.jpg[/img:2297hy4t]
Deep inside, the two pickguards (protective wrap on)
[img:2297hy4t]https://lh3.googleusercontent.com/_ycCeFTJWlq8/Tc2SB5ve0DI/AAAAAAAAAiM/z0L9vcEpTTo/s400/IMAG0036.jpg[/img:2297hy4t]
And the pickups!
[img:2297hy4t]https://lh6.googleusercontent.com/_ycCeFTJWlq8/Tc2SK-2Je4I/AAAAAAAAAiQ/CFqNtMlCPqg/s400/IMAG0031.jpg[/img:2297hy4t]
All laid out on the floor, it looked like this:
[img:2297hy4t]https://lh4.googleusercontent.com/_ycCeFTJWlq8/Tc2SZdnVJYI/AAAAAAAAAiU/c0L5xXD13dU/s400/IMAG0037.jpg[/img:2297hy4t]
That's all the inspiration I needed

Let's go.
[b:2297hy4t]Realization[/b:2297hy4t]
I've taken the guitar to a friend of my fathers that had all the needed tools and expertise to do this. He has created a few guitars as a hobby so he knew exactly what he was dealing with. Well, more then myself

First, removed the strings and unsoldered the pickups.
[img:2297hy4t]https://lh6.googleusercontent.com/_ycCeFTJWlq8/Tc2SfYUnu7I/AAAAAAAAAiY/nU4ixe4MOig/s400/IMAG0039.jpg[/img:2297hy4t]
The idea was to measure and route the pickguard first, as routing the body wouldn't be a problem since any irregularities would be covered by the pickguard. First we put some tape over the pickguard: we could draw on it, and it would be removed with the protective wrap in the end.
Here's a pic with the custom pickguard on, and one after the new pickup route has been drawn. The G and B strings are there to help align the pickup properly.
[img:2297hy4t]https://lh4.googleusercontent.com/_ycCeFTJWlq8/Tc2SzWZ5szI/AAAAAAAAAio/hwCVGSJri6c/s400/IMAG0040.jpg[/img:2297hy4t]
[img:2297hy4t]https://lh3.googleusercontent.com/_ycCeFTJWlq8/Tc2SwXdAckI/AAAAAAAAAik/nqBulEFXKy0/s400/IMAG0041.jpg[/img:2297hy4t]
After some drilling to see how the material fares, the routing started. [img:2297hy4t]https://lh5.googleusercontent.com/_ycCeFTJWlq8/Tc2SwdcKEuI/AAAAAAAAAig/bXia74pkdQI/s400/IMAG0042.jpg[/img:2297hy4t]
[img:2297hy4t]https://lh6.googleusercontent.com/_ycCeFTJWlq8/Tc2TAp5SSwI/AAAAAAAAAiw/AkpLtZiG0dY/s400/IMAG0043.jpg[/img:2297hy4t]
We routed the body on a simple table router. I forgot to take any pics on that, sorry. I wish I had, as you'd be able to see just how much body wood had to be removed. Basically, only that narrow strap of wood that is normally between the pickups was in the way. Such a small amount cannot affect the resonance of the bass in any significant way!
As for the neck pickup wiring channel, a new channel didn't need to be drilled. After the routing there was a single route that spans all three pickups, and neck pickup wiring could be sent through the old neck pickup channel with no issues whatsoever.
Also, at that point I've realized that the mod is reversible: remove the pickguard, move the pickup to the old location (no re-wiring required!) and just screw a regular pickguard to cover the route. Nice, isn't it?
Here's a pic after the routing is done. We spraypainted the route black so it wouldn't be visible.
[img:2297hy4t]https://lh3.googleusercontent.com/_ycCeFTJWlq8/Tc2TGuxTTTI/AAAAAAAAAi0/8bz76ZE2AMY/s400/IMAG0046.jpg[/img:2297hy4t]
Here's how it looked in the end, with pickups in the new location.
[img:2297hy4t]https://lh3.googleusercontent.com/_ycCeFTJWlq8/Tc2TTQZ8dGI/AAAAAAAAAi4/cYAZYDKcjbk/s400/IMAG0047.jpg[/img:2297hy4t]
Once it was cleaned, the pickguard put on, and the protective wrap removed, it shined:
[img:2297hy4t]https://lh3.googleusercontent.com/_ycCeFTJWlq8/Tc2Tc0pWfNI/AAAAAAAAAjA/dsW5SyJ2XtA/s800/IMAG0049.jpg[/img:2297hy4t]
[b:2297hy4t]Result[/b:2297hy4t]
Better then in my most optimistic dreams.
Is it aggressive? Oh yes. It's just in that sound area I anticipated, and GOD that low B became so alive. Thunderous, groundshaking, and yet precise and rich. What you normally slap on the E string sounds so awesome on the low B: just powerful, not muffled or over-bassy at all, just powerful.
Does it sound like a Stingray? Well, no, but I did have a few moments when I was doodling while reading something and got struck by a sound you'd expect on a Stingray.. So the potential is there. But remember, in order for something to be better, it also has to be different

, and besides, nothing is more alike to a Stingray then a Stingray. Any change, fanned frets included, changes the formula for better or for worse.
The stock preamp is not very suitable for the mod, it's gentle, almost transparent compared to the animal the bass has become. My AB-II has a very aggressive Aggie preamp so maybe I'm not realistic in comparing the two, as the AB-II is my first active bass. Either way, changing the pre on the C2 might be a logical next step. Preferably to a John East 2 band EBMM pre, or an Aggie. It's a long term plan, and so is changing the hardware to all black

I've had a big gig yesterday, and the C2 was in the spotlight. My band, who have liked to Combustion as-is, were blown away by the change. If I get some action pics or a clip I'll sure post them.
Sooo that's it. I am really happy I've done it, and I hope I've sparked some interest in this mod.. Maybe one day we'll see a stock model like this. Even if not, it's an inexpensive and reversible mod, so why not go for it?
Cheers,
Bo