I don't know that I would try a hair dryer to remove the decal from the foam. You could end up melting the foam. You could also end up taking some foam with it if you just try to peel it off, and any kind of solvent that will loosen the glue will probably also melt the foam.

Covering it may be a better way to go, but you'll be adding some weight, and all on one end of a wing.

Fly it first, and then worry about what's written on it.

Good luck