[Stealth]

You're going to want to learn to comfortably disassemble/reassemble the mechbox first before diving into FETs, wiring, testing, etc.

First step is to get a new set of trigger contacts, then address your other functional problems, if any (ARL, motor, etc.), then step into a FET. The best upgrade approach is to always upgrade or change one thing at a time so you isolate variables. I feel like you're trying to address everything in 1 shot - which is an honourable effort but unless you're an experienced gunsmith using parts you use all the time, it almost never comes together the first time.