When I tension to tune - the bridge posts are backing out of the body. Probably need a shim of some kind I reckon? I was thinking of shaving a toothpick but thought I'd ask for ideas here first.

THANKS GUYS! I gotta tell you every pro musician I've played with is "335 bass? I didn't know they made that..." only 2 out of my entire group of musician buddies had ever seen one. Excited!