From the factory the '60-'66 Chevy trucks had a rubber half mat from the top of the firewall to the front edge of the seat. The floor pan below the seat did not have any covering. The entire floor of the cab was painted the same as the interior of the cab. The portion under the factory floor mat was covered with an impregnated sound mat direct to the floor, followed by a white foam mat and then the factory rubber floor mat.
There are many carpet options from the aftermarket truck suppliers, however carpet was not an option from the factory or dealer. Carpet and mat hold moisture for an extended period of time, whereas the rubber mat will not absorb and hold the moisture. Upon purchasing a '64-'66 Chevy truck the first thing I do is pull the floor covering and thoroughly clean the floor pan. At that time, I am able to determine the condition of the floor pan sheet metal. I then properly prepare and coat the floor pan, where necessary with POR 15 (or your product of choice).
The floor pans deterioate over time due to the dirt and grime that accumulates in these areas, as well as the cab corners, coupled with moisture, thus rusting the sheet metal. Preventative measures will eliminate the majority of this process. Maintenance, as well as a good cleaning and surface protection, will prolong the integrity of the floor pan sheet metal, regardless of the floor covering being rubber or carpet & pad.
Good luck with your project.
Tony
