First off, welcome to the site. I am in about the same place as you in replacing sheet metal on my 66 and I, too, am pretty new at mig welding. I really appreciate the great pictures you took of the rockers and floors. It helps me get a good perception of what's in store for me. I haven't removed the outer rocker yet but my rust area seems to be very similar to yours. Good luck on your progress and I'll be checking in.
