I don't understand this post at all. Does it work or not? Why did you take it apart? There is nothing tricky about the construction of a Gravis Gamepad.
Back around 2007, I found the gamepad in (seemingly) perfect condition in my retrocomputing collection. I tried using it with Descent (just to see if I could play it easier), but that didn't work. One of the buttons would not respond. I figured there was a cold joint in the solder points on the board (not a bad assumption given how SOME of these retrocomputing items were previously constructed.) But it didn't fix anything.
I put it away for a long while. In 2017, I got a new retro computer, and I had a Sound Blaster on-hand to test its capabilities. I got the Gravis Gamepad out, and tried it again. As I was testing it, I realized it WAS in fully-working condition, but only when the cable was pulled straight. The best assumption I could make was that there was a break in the wire for the previously-mentioned button. It doesn't help that the cable is bent rather strangely in the controller's case. I took it apart, hoping that I could cut the cable behind the break, and reassemble a new connector with crimping tools.
I wasn't able to. (My skill wasn't the problem. It was the crimping tools, and the wiring. A few manufacturers I've tried don't make it crimp precisely enough, or it crimps it too hard, severing the connection. Plus, the wiring inside the cable is VERY frail and thin.)
Anyways, I'm selling this off because I have a better controller (One that seems more Nintendo/Sega-like), and
I'm selling it for $15, but I can haggle for a lower price.