[quote="Dragonlord":3odgrbj2][quote="Dragonlord":3odgrbj2]If I have someone locally drill new holes, can't I have the Mach II selectors on individual switches, just like the mid freq switch?[/quote:3odgrbj2] Last question before I proceed with the upgrades... a preamp (most probably glockenklang and not aggie) with 3 frequency knobs, a volume knob, a 4-way selector, a mid selector switch and two machII switches should fit in my prima's cavity if I drill new holes, right? It doesn't have the separate battery compartment.[/quote:3odgrbj2] The only way to answer that is to have all the components on your workbench with the cavity open. Install as many components as you have holes for and then see where everthing else will fit. Worst case, you rout in a separate battery compartment like the Gotoh fliptop style.

[quote="Dragonlord":2q11dz54]If I have someone locally drill new holes, can't I have the Mach II selectors on individual switches, just like the mid freq switch?[/quote:2q11dz54] Last question before I proceed with the upgrades... a preamp (most probably glockenklang and not aggie) with 3 frequency knobs, a volume knob, a 4-way selector, a mid selector switch and two machII switches should fit in my prima's cavity if I drill new holes, right? It doesn't have the separate battery compartment.

Thanks for the reply! If I have someone locally drill new holes, can't I have the Mach II selectors on individual switches, just like the mid freq switch?

You should have no trouble since the OBP-3 can run off of a single 9-volt battery. The pickup switches will need to be mounted on push/pull pots.