I have a Roland AC 60 acoustic guitar amp, which can use up to 4 footswitches to turn various functions on and off. The manual shows it with one Boss FS-5L and three Boss FS-5U pedals, each one costing at least £25 quid, plus two PCS-31 cables at another £25 quid each so we are up to £150 quid just to turn a few effects on and off!
I don't think that's a great deal, so it seems to me that it would be fairly straightforward to buy 3 momentary normally on SPST switches, one DPST switch, an LED and a resistor for the latched one, and stick the bits into a dead Behringer footswitch which is currently cluttering up the spares cupboard. A couple of lengths of dual core cable and a couple of stereo 6mm jacks and Robert is your relative.
Surely it can't be this simple - what have I missed?