im assuming your using enamel not acrylic then? then i see what your saying the colors will kinda float on the top of the water..hmmm not a bad little trick i'll wait to see some step by step pics so i get it right!! Sounds pretty cool though... You know those decals would fit that sleeper pretty well
just sayin. you could always get the decal sheets and print your own or have them made to like a vynal wrap in the size you want.. Little more pricey but worth it. look at Russ's toy hauler!!!