Paint advice needed

When I do the jams, engine compartment, bottoms of hood and decklid, trunk and interior floor pans of my 65 Barracuda, I will buy a gallon of single stage urethane. I'll do the interior floor pans last in case I run low on paint at that point. I want the stuff that will show to look nice and shiny, but as long as I get some color on the floor pan....that will be good enough. Carpet's gonna hide it anyway!