I'm on the same boat as you, my grip frame screw is stripped, I wanted to use a am/mm rail on it but I might just clean the valve, replace o rings and use as is. It's killing me to not be able to take it apart yet though, we'll see.
I'll join the party with the grip frame screw. I ended up dremmeling the head off and sliding the frame/rail off. Now I'm trying to get one of the ASA screws out.
I was a little peeved when I first got the box. I picked it up, heard the barrel rattle on the body and realized what i was in store for.. Got a good amount of marring on the drivers side of the body due to the barrel threads. Plus the condition in general wasnt "good to very good" like stated. Oh well, looks like I now have my first mag build.
I had to take a drill bit just slightly bigger the the hole in the frame and drill out the head of the screw. Then I soaked the screw in PB Blaster and used my batt. drill to work it in and out until it came out. But just "bump" the screw FWD&rev until it moves. This also works on the asa screws. It's still spooky until the thing comes out.
I took the road least traveled...now where the hell am I ?