IB-5 Pickups/Cavity Size

Hi Guys
I have built a number of Pit Bull guitars and been very happy. I have started playing bass and want to build the IB-5 kit (5 string bass). I am quite familiar with normal guitar pickups and cavity sizes etc. My question is, with the IB-5 pickup cavities, are they some kind of standard size such that I could upgrade the pickups if I wanted? Cheers Steve W

I built one quite awhile ago and from memory I think the supplied soap bars had the same dimensions as other brands.
I wouldn’t take it as gospel. To confirm maybe send the pit bull team an email to see if they can measure for you.

Many thanks - Will Do