Coiz- you're doing a great job. Every time I come back to this build I am excited to see how far it's come. Much like everyone else, I'm very much looking forward to seeing it finished, and yet dreading that at the same time. It will mean having to find a new build to follow... :-)
twildt- the spray in foam would work. If memory serves Ford was using it in their frames a couple of years back. Not sure if they still do. There are some issues with that though. First, you would have to make sure the inside of the frame was completely rust free BEFORE applying it. Other wise you'd just trap the rust in there and it would continue to eat your frame. Acid dipping is probably the best way to do that because it works well, and is cheaper than all the over the counter stuff you can buy to do the same job yourself. It's also much quicker and cleaner for you. Personally, I would dip it in acid, then use a rust stopper like rustoleum or POR 15, and then I would fill it with foam. The nice thing about the foam is it also quiets down some road noise. Not such a concern in a Jeep, but every little bit helps.
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