undercoat topside floorpans?

yep, driver, i've made my own floor pans, welded in, may be awhile before it gets carpet , gonna drive it. wondering about using bodyschult or bedliner to seal the inside (top side) of pans, i've already applied good coat of equipment enamel, but would like something more, i figure carpet will go on top of the bedliner type material no problem. ( sorry purist) if factory used undercoating on underside, maybe it would have been good to apply to top side too !???? i've used bodyschult years ago and its a great produst, someone stole my gun, wonder how the bedliner is a car works here?????