Today I mounted a GG&G rear sling attachment point on my MR1, which might not be a big deal other than they don't make one for the MR1! (and neither does anyone else that I could find) Instead I took a chance and ordered one for the M4. All that was necessary was to drill two small holes for the dowels to pass through, and take a little metal off the sides where the MR1 body is a little more narrow, and take a little off the leg length. I would be remiss if I failed to mention the dowels do not go into the back of the receiver, however they pass completely through the sling mount, and the sling mount is held in place by the trigger housing. Also, I have replaced the original stock on mine with a different Benelli stock. The instructions say I can post a photo - hopefully that is correct, it made a pretty neat installation.GG&G 005.jpgGG&G 004.jpg