I re-did my firewall on a project I’m working on. After replacing some of the metal I sanded it all down and saw some small spotts of rust in the existing metal. So I sprayed the old and new with rust converter so the rust would not spread until I get back to it. Now I’m getting ready to use body filler on the welds and spray with epoxy primer. What prep do I do before applying filler? Thanks.:confused:
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