I'm getting ready to blast and paint the cab of my '51. I'm not sure if and what I should use under the cab. I thought about spray in bedliner or some sort of a scuff-proof paint. Any ideas or does protecting the bottom of the cab matter?

I am also thinking of welding the sheet metal parts inside the cab (for tranny access and master cylinder access) in place as I will be moving the master cylinder to the firewall and cannot see why I would need to access the tranny from inside the cab. Am I overlooking something in doing this?

Thanks!