Used a little klean strip rust converter (good stuff)on the back of my bumper and it worked great.So me thinks ill use it on my frame.Cleaned degreased sanded rinsed all the good stuff.went to get some more converter and they only had the mar-hyde converter in a can.My god that stuff suxs,sprayed it on and it jumped right back off looked good at first, but got up the next day and blew 90 percent right off with compressed air looked like a bad peelin sunburn. just got my por 15 catalog in but now i am scared,looks like the guy tryin to get it off the fender in the (why do they do it) post had a hard time removin it,but i am gun shy now.Never used any rust stuff before always just primed and painted.help me feel confident about this stuff and if it doesnt work i can blame u guys here .j/k thnx all for helpin me keep my state of mind!