I bent mine out of the same gauge as the original one. Water pooled after the cowl drains (1975), or from any other source, failed. I bought the Cruiser with the original floor mats - free to anyone who wants to pick them up. The truck was wet under them when I bought it.This is a common failure point... worth inspecting for signs of failure which could potentially become a safety issue. Yours should be good for another 30 years.
I happened to repair mine with +/- 6” of 1.5” bar stock that was about 1/4” thick. Welding 1/4” to 1/16” isn’t without its challenges, but it’ll never fail again.
Yes, the driver's floor pan needs work.
I grind for prep, but not for finish. It seems more true to the integrity of the truck - along the lines of keeping the hair grey / no toupee.