Just got an answer from Kevin Brubaker:
A 3/8" post is what you need to get for the replacements.
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A 3/8" post is what you need to get for the replacements.
Just got an answer from Kevin Brubaker:

In a nutshell yes!!!! The Brutes were made to be upgraded with High End Pups and Pre. However from what I've heard the newest Brutes with the coil splitter sound damn good.What I don't understand is why you guys are doing electronics swaps... are the Barts really that much better than the stock pups? Cuz I do really like the tone I get from my JJX5 as it sits. All great except for the dead treble pot, ahah.
Would also love to hear it when you're done Phillybass!
FYI/heads up, eBay has a early/first electronics version jjx5 in red with black guard for $300 shipped! Slap in some higher quality pups and pre and have a superb quality j bass for cheap. Mentions a chip on the back and a bow in the neck (maybe just a truss rod adjustment needed by someone with the know-how???). Someone needs to check this out.
Hi, just made another thread but wanted to ask here too.
Do you consider the bridge alignment and the quality of the pickguard of thi Brute Jjx-4 is good/on pair with yours?
Thanks