[quote name='Shaggy' timestamp='1338573548' post='1676716']
The P-retro is a good call, but if it was me I'd fit a piezo bridge (I know there's a Fender-fit one cos I used to have one, I think they can be had around the £50 mark now....).
Gives you that nice, woody acoustic-y sound perfect for fretless, that can be EQ-ed to sound quite "Jazz nasal", and usefully different to the P p/up.
There may be a way to do without having to route a battery compartment, but if unavoidable I'd far rather route the back than the front - don't touch that!!!
[/quote]
This - you may find that a PP3 battery will fit [i]somewhere[/i] under the scratchplate of the bass.