Today i recieved my USB SNES controller, i will take it appart and modify it this week.
I made a quick and dirty 'diagram' of the circuit board connections in MS paint to help me decide where to cut the PCB without screwing it up, i wanna do it right the first time ;). I'm probably not going to use the start/select buttons though.
(Red dots are GND, yellow are the signal lines)
I think the following way to cut it will work fine, it's probably best to solder directly to the pads. The middle section is useless (in my case) so i can throw that out. Ofcourse i need to reconnect some ground planes since the connection got cut.