[quote="evilgus":l1vx6ug1]Ah, but given it's a different design to my ABII and has two less frets, surely the headstock should still be a bit closer to the body? Yes, it would still be a 34-37" scale length bass.

EG[/quote:l1vx6ug1]
The only thing that would get the HS closer to the body would be a shorter scale, not less frets. The amount of frets will never affect scale length. You could have a one octave 12 fret Z2 and it'll be the exact same size as your bass.

Take for example your bass Evil. Remove the highest 10 frets on your 22 fret Z2. The bass wouldn't get shorter, it would just have less frets.
Given it's a different design the only way for it to be shorter would be if Sheldon shaved off an inch or 2 of headstock. There's not much room to shave the body because on both models the B string is at the edge of the body.