peavy bxp vs a squire vm jazz bass. which is easier to mod
 

both on craigslist for 180. wanting to get one to start moding for fun. which would be the eaiser one?

First thing, don't buy either one at that price! I have an all black BXP I could do better than that shipped.

IMO, probably the Squier, because more parts that can be used with a Fender can be used with a Squier. Depending on the part, it may require some, little or no extra work to fit.

main thing im thinking is pickups and maybe putting in a active 3 band eq. maybe bridge and drop d tuner later

Yeah, you should be able to find drop-in parts to fit the Squier. There is a thread dedicated to this, entitled "Perfect fit replacement parts for Squiers", or something similar.

If I were going perform those mods, I'd choose different basses. You'll be putting more dough into either of those basses than they're worth. But if you're committed to do this, either bass will be fine. Standard parts will fit both. These basses do have greatly different design, though. So choose the one that feels better to you.