[FC] 1963 FC- repairing/replacing front floorboard- FCs used by Edison ?

[David Houston]

 I saved a '63 FC from salvage last Jan. Upon removing the amateur carpeting in this former Pa. van, the most significant rust is in the front floors and bondoed rockers. Is the Floor removal a difficult job due to the unibody design? Is there a replacement available? My rockers were repaired with fiberglass/bondo ,but it's showing it's age. The rest of the van's floors are decent. Also, I discovered that early '90's S-10 rims fit my front axle. I was considering plywood as a floor replacement. 
Another discovery is that my van had been painted the same yellow color that electrical power companies like Edison had in the 1960's. Did Pennsylvania Edison/electric use FC's? Greenbrier's?