Made a lot of progress tonight. Yesterday all of my parts came however, I had ordered a crimper and some wire from Amazon that arrived yesterday that was the wrong kind. I did not realize I needed a specific type of crimper for these pins but I did, and I just had a standard crimper so that didn't work. Also the silicone wire I ordered was ass. I hated how flimsy it was and the casing was really thick. And it also kind of "peeled" so it was hard to get a flush cut of the casing when stripping wire. So last night I ordered more stuff on Amazon and it came this morning so I finally had some time tonight to mess with it.
The crimper I needed was this kind here, and there is the little wire kit I got too.
So the general gist of what I needed to do was create a 6 pin molex connector to connect to my control panel (where the kick harness goes for JAMMA boards) and then wire 4 of those to pins 25 and 26 on both top/bottom for buttons 4 and 5 for P1 and P2, and then I had to wire up button 6 for both players and that goes to a screw terminal on the pi2jamma.
Here is a pic of the little .100" terminals that go into the molex connector. These were pretty hard to do just being so little and I don't have Trump like hands. But I managed. And the other terminal is what I used for the screw terminals so it wasn't just raw wire.
And here is a .156" terminal that goes into the empty slots on the JAMMA harness. These look identical to the .100" molex ones for the most part.
Here is the JAMMA harness for pins 25 and 26 on the top side of it, for P1 buttons 4 and 5. It is the white wire and black one to the right of it.
And here is the other side for pins 25 and 26 for P2 buttons 4 and 5. it's the green wire and the yellow one to the left of it.
And then here are buttons 6 for both P1 and P2 in the pi2jamma.
And then here is the actual molex connector plugged into the control panel. I don't know if you can tell, but the blue wires on the control panel all have another color on it like a small spot, and I tried to match those up except I had to match brown with white. But the rest pretty much match up.
Tomorrow I plan on going to Home Depot and getting a bunch of zip ties and zip tieing everything to the current wires running to the JAMMA harness so it will be much cleaner. Then I plan to mount the pi2jamma on the side of the cabinet too where the JAMMA PCB's typically go. So everything should be super clean tomorrow unless I don't have time and I will post some pics of it cleaned up.
Everything is working fine control wise though so that is all that matters in the end. I still plan on getting my monitor rejuvenated and then it will pretty much be finished.