OK, I'm sure this has been asked before, and YES, I tried searching, but not much luck on my specific question. Tonight, at work, I swapped a gen 2 and 3 upper and lower on 2 guns. One thing that's already baffled me, is gen 2 guns are supposed to only have 2 pins, but mine had 3, so the swap with the trigger set worked too. So, I wanted a gen 3 frame for the grooves and rail, but I wanted to keep my trigger set (modified trigger, and lighter connecter), and I didn't feel like fooling with swapping sights, so we swapped uppers too. Anyways.................everything lined up. Will this work? It cycles just fine, and everything seems to work. I can only tell a subtle difference..........the front block, and the extractor. Need some quick answers cause I'll be shooting an IDPA match this weekend.