Good point, so well worth checking!

On my Strat Mini, it could be done, with approx 1cm of wood left between the necessary cavity depth and the rear of the guitar. You may have to drill out the bottom of the cavity slightly to do so, as it's too much hassle taking the pickguard off mine to check.

But the PBG kit may have a thinner body than my Strat Mini, so if emviar thinks its possible and wants to go that route, then definitely measure first - and double check.