"The problem with backing it against the other side of the frame would be in many cases the rivet is inside of a channel or something is obstructing." ?????? Don't get that statement?
The rivet you are upsetting ,that is inside the channel, is not on the OTHER side. As far as an obstruction for the "jack" on the other side, just put a plate across the channel, or a block or solve that issue somehow when you get there. They don't seem to have that problem in the video. However hard it is to get to the rivet, it's the same problem for any bucking bar/tool method. You have to get the bucking bar tool head on it.
C clamp would not seem to be "fast acting", meaning you ain't got time to screw around clamping when a rivet is hot and ready. That's why they have to heat it in place. Heating a frame or welding on a frame is not good for it as explained right in the TF maintenance manual. Good luck on your endeavors. Denny and Grigg have the experience on this one. Follow their advice. I'm a Stove Bolter.
