Responses are all over the map, 'cause we really don't know what the floor looks like.

In general, I'm with Scott; try to save what you can, BUT I'm not one to bandaid stuff either so it really depends whether the floor is

A: rust free for the most part (i.e. still has paint on it) with a small area or two of rust and/or crustyness

OR

B: surface rust on all the lower surfaces with pitting all over the place but only pinholes in a few areas.

With A, I'd either clean up and save the whole thing or cut and patch only where necessary using proper butt welding procedures. If using patches, I'd prefer rust free original donor panels

With B, I'd probably replace the entire floor at the factory weld points.



Dave