64 valiant floor pan rust, practical fix?
Wire wheel, then clean with phosphoric acid (concrete etch/prep) or make up a batch of evaporust (threads about it here and on fbbo) that would take just a few hours to get rid of the rust.. seal the rust with corroseal.. and patch any holes (can't tell how bad it will be from the pics)
How you patch the holes is upto you.. if it's just pin holes i would have no issue using some flexible filler.. bigger spots you could patch over with metal/adhesive or seam sealer.. main thing is to clean up the rust and stop it.. how you patch.. meh.. if it's not a show car and you are happy with it, let it fly..
P.S. some of the guys here will tell you to replace the floors which in a perfect world is fine, but some of them had a cut up stop sign for a floor in the past themselves :)
Being from michigan those floors don't look bad...
Here's the thread for rust removal stuff... it will make life easy. don't forget to clean under the floor and seal it also once it's cleaned up.. i use brush on rustoleum black, but spray looks better.
https://www.forbbodiesonly.com/mopa...better-than-evaporust-and-10x-cheaper.299605/