underside paint

getting ready to paint the inside of my quarters on my truck. below the bed floor. Will not be seen. any tips on getting something that will last if the area is just cleaned up nicely. or should i strip it all the way down like everything else i did. going to be a driver. but an occasional show also

Thanks.

(por 15??)

I used a product called "zero rust". It is a paint with what appears to be a lot of resin in it---looks good, seems to stand up very well, and its a one step process that does not need topcoating.