I know the hazards with this decision but it has been made. I'm installing an under folder on a stamped reciever. I do not want the reciever extension avaiable from Noveltyguns as this will not allow it to work over the mag. Am I right about that?

Anyway It doesn't look to work with a mag in. So that leaves the option of drilling? cutting? or drimelling? holes for the rear trunions? What I'm looking for is some exact or at least in the ball park directions and measurements for this install. I understand that a plate will also have to be welded in place at the rear to close of the reciever. Thats easy for me. I do have access to some nice tools and equipment that will help. Any info is gratefull.

Thanks,
Akginmaster

The adapter will not allow the stock to clear the mag when it folds.
What you want to do is a lot of work.
Remove the stock and cut the rivet heads off the rear trunion. Drive the rivets out and remove the trunion. The rivets are in a different position on the underfolding stock trunion. So weld the old rivet holes in each side of the receiver up and grind smooth inside and out. Drill new rivet holes,drill new holes for the underfolding stock mechinism and notchs on each side of the underfolding stock holes. Rivet the underfolding stock trunion in the reciever and install the underfolding stock. Reblue the receiver and rivets.

Thanks for the reply, but not sure that I have the under folding rear trunion. The old mak 90 trunion is where the top stock scew goes in (If I'm on track, Right?). I was examining this and correct me if I'm wrong, I was going to leave the old trunion in and remove the tab for the top screw of the stock. I was thinking that I could weld a plate from the bottom of the exsisting trunion to the floor of the reciever to act as the catch for the pin that stops the folder from moving. The plate would need a groove. Then I could weld a rear cover plate to close off the reciever. That way I could avoid removing the trunion and all that welding, finishing and reblueing.  Just weld a plate in there and drill one whole thru both sides. Looks like I've got the room and the folder will clear the mag.

What do ya think? Sounds like it would work.