I apologize for the use of the word of slider instead of wiper. I have no idea where that came from.
Having the circuit drawn out (or a picture of the wiring diagram) and following it is important. Sometimes the top or bottom of a pot will not have a wire attached. (Note the Tone pot wiring in the diagram I previously posted.) When running into a problem tracing the signal path from input to output usually reveals the problem. Sometimes it is as simple as a misplaced wire or a stray wire touching ground or another part of the signal path. We called those 'cats whiskers' and they usually showed up at terminal strips.
Personally I stay away from extra ground wires unless there is an issue. It is possible to introduce a ground loop which will give you a hum. Keep at it - I am looking forward to your post where it you having it working like you want.

Having the circuit drawn out (or a picture of the wiring diagram) and following it is important. Sometimes the top or bottom of a pot will not have a wire attached. (Note the Tone pot wiring in the diagram I previously posted.) When running into a problem tracing the signal path from input to output usually reveals the problem. Sometimes it is as simple as a misplaced wire or a stray wire touching ground or another part of the signal path. We called those 'cats whiskers' and they usually showed up at terminal strips.
Personally I stay away from extra ground wires unless there is an issue. It is possible to introduce a ground loop which will give you a hum. Keep at it - I am looking forward to your post where it you having it working like you want.