 
		The ground lines converge at the 1/4" phono jack chassis lead.
The neck pot controls volume and balance. The bridge pot controls bass and treble boost / cut.
Neck pot markings:
		(on the circuit board)
		BEQ2-BAL (RIGHT)
		revB 20150617
		(on the pot case)
		B504
		C504
		A504
		The pot has 12 pin connectors.
Bridge pot markings:
		(on the circuit board)
		BEQ3 system - B/T (right)
		revC
		3EQBBT - CF1 2S 01 20150504
		B/T1
		VR
		(on the pot case)
		B103
		C103
		The pot has 6 pin connectors.
TMB EQ circuit board markings:
		BEQ2-BT_MAIN revF 2015-04-10
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You may contact me at kevin@kevinsworkbench.com