I have done several, down load these free instructions. i recommend several things for getting the best results with a minimum of effort and complications. The trigger spring for 2 to 3 pounds has worked the best, I put the heavier hammer spring in for several reasons. Smooth all the mating parts take off the seam [ what usually causes the problem] first with a fine cut needle file then with the AR stone, DO NOT change the angles just smooth the surfaces to glass slickness. For the instructions go to:
http://www.bellmtcs.com/store/index.php?cid=456