Hi. I want to make THIS booster and fit it in my guitar. I would replace one of the tones in my strat with the boost pot from this and use the other tone for all 3 p'ups. My questions are:

1, What would I need to do to remove the LED from the circuit
2, And if I removed the LED, there would be one pole left on the 3pdt switch. Because there is no stereo jack in use, how would I connect the battery to the spare pole to stop the battery being turned on permenantly.

1. don't wire in the LED, its just a matter of offboard wiring

2. drop the footswitch and get yourself a regular DPDT toggle switch
also, its ill advisable to set-up circuits like that so you disconnect the power....it usually leads to an annoying popping sound whenever you turn it on. a stereo jack is like $1.5

also, you might actually want to leave it always on and just roll off the boost when you do/don't need it. Having that in the guitar will act as a buffer which will give you a more consistent sound with different cables/longer cables
In that case, how would I use the output jack to turn the battery on/off? On their schematic the input jack is the stereo, and how you would wire it...
you would wire the negative terminal of the battery to the stereo part of the jack. Since the cable is not stereo, this will be connecting it to ground.

A battery cannot have a flow of electrons without both of the terminals being in use. So the circuit won't get power until a cable enters the output jack giving the negative terminal of the battery a way to flow
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