imo. as far as difficulty. I would not use any rust converter at all. sandblasting will take care of all the rust. clean em well with wax and grease remover, and put your 2k dtm epoxy on em. Per spec sheet when the epoxy is ready, shoot just a hi-build 2k primer. a few coats max. Let dry at least 24 hours to allow for shrikage. lightly sand with approx. 400, since your not going for full on body panel type perfection. should be plenty smooth and shoot your color. you don't need sealer on top of 2k primer. I think you will be happy with the results. If you rub through the primer, rescuff the entire wheel again, with 180 clean again and shoot a few more coats on. bottom line is you want a nice even finish throughout to put your top coat on. All sanding will be done by hand of course, and again, make em nice, but you won't be able to get your standard, blocks etc in there, wear gloves to prevent hand oils etc getting in any step of your paint and prep work.