Are you thinking about nutserts in the frame or welding threaded bungs into the tubing? May be able to cover the burnt paint with the bracket. A lot of side load (away from the frame), not a big deal against the frame. Not sure of the style of (bolt-on) bracket you are planning but if at all possible make it so bolts go thru both walls of the tubing, in my view; any other method will not live. May work if bracket bolts to both side and bottom walls of frame tube, made from angle or a piece cut out of heavy wall tubing.