Well, Im no expert but I did wire one up for my Mame machine. As I remember there should be 2 sets of pins (set1 and set2). You need to short a pin from set 1 and a pin from set 2 to creat a key stroke. What I did was download a keyboard tester (google or dogpile search) pluged my keyboard (or what was left of it) in and just started going through the pins and write everything down in a chart. BTW it only needs a short for a second, just like you would hit a key. Now remember that all the keys will be in there so if you short 2 pins and nothing is typed you may be hitting 'esc' or 'shift' or something like that. It shouldnt matter what size of wire you use, I used solid core cat5 wire (just one strand) to short them for testing.