undercoat topside floorpans?

A friend of mine has used Armour Liner on several vehicles of his own and for customers. They make it in traditional Black or they have a clear version which can be tinted with a quart of single stage paint if you want a color matched version. He has it inside the tub on his CJ, and has done several cars for a local guy that he paints for and has had good luck with it.