Swapping pickups in Aerodyne Jazz V Bass
 

Hey guys

Recently bought an Fender AJB-V from Japan. I was wanting to swap out the old pups for Bassline V's but when I bought the basslines (off eBay) I saw they were way too big for the pick up cavity for the neck and the bridge pickups.
I've been communicating with the eBay seller and he says that all the others (nordstrand, fralin, etc) are the same size as the basslines i.e. none will fit in the AJB-V's pickup space.
I measured the pick ups on the bass and they are the exact same size as a normal 4 string jazz pick up. Very strange.
The seller says I could swap out the 5 string pickups and put in new bassline 4 string pickups and it should be fine.
Is it ok to do this?