I'm pleased to report that GunGeek's dad and I successfully redeemed a Universal paratrooper carbine. The problem was that the original aluminum mag well/trigger housing cracked, and recracked in a different place after being welded together. GunGeek's dad said screw it and bought himself a nice GI for much more $$$. But thanks to a stripped M2 trigger housing from Centerfire, the components from the old one, a flathead screw to replace the old forward retaining pin, and a lot of work by his dad to remove and reinstall the safety and mag release, the trigger group went in the carbine and it worked. (and then they learned that they could have gotten a complete trigger housing for $50, and didn't really care about the $20 difference) So if anyone has problems with their universal trigger guard/mag well, this will do the trick.