Just got a hand me down 1A2 L from a guy that Just returned from the desert. He had to do some quick modifications to it to mount it on whatever he was shooting. Basically just removed the mount attachment that would connect to the swivel stud. There appears to be a shim (steel) that fits between a top and bottom tab that has also been removed. I've been trying to find a diagram to find the proper names for these items I'm in need of but have had no luck. Is contacting Harris my only option?? Thanks, CD