I'm starting up my business of making custom basses and guitars. I have suppliers lined up, business ready, but I lack a few details... 1) Where can I find threaded inserts for mounting behind a control cover/battery cavity? I hear hardware store, but there has to be a supplier out there who isn't as shady as my local hardware store. 2) Where can I find the larger inserts for necks along with machine screws? 3) I have accounts set up with Allparts, WD, Davitt and Hanser, EMG, Moses and order whatever else from Stewmac or LMII. Should I be in contact with anyone else?