mounting/channeling body

[kamaroman68]

Hey everyone. I don't know if I'm having a brain fart or what but maybe someone can give me a hand. I ordered a max g frame from art morrison. What I'm looking to do is channel the body over the frame but in a bolt on fashion. The frame rails are 2 x 4 .120 wall steel. I would like to put the channel over the frame rail and bolt it down. I would like to use 1/2 inch bolts. The problem is obviously I cant just tap the hole in the frame. I tried nut serts but they spin at 4o ft lbs of torque. I tried another product called weld nuts with bases but the threads ripped out of that product at 50 ft lbs. Plus I would like it to be repeatable in that if I take the body off I know the threads will be reusable. The last option I am about to try is welding some 1/2 - 13 grade 8 nuts on to a grade 8 washer. It would then pass through the frame rail until it hits the washer. I would then weld the washer to the frame. Will the temperature from welding affect the strength of the nut, washer and bolt assembly? Any other ideas on how to do this ? I realize it probably does not need to be as strong as I want it but I tend to overbuild so I know I will not have a problem later. Thanks Chris