Glassing over Painted Glass

My friend painted an old fiberglass board for an art show using acrylic paint on the deck, we want to glass over his artwork to be able to ride it.  There's no paint on the bottom, fins are glassed in as well.



I'm looking for tips to glass over a previously glassed board and not ruin the paint job.  Would this require sanding?  thanks!



I would just spray a nice coat of acrylic spray clar coat over it and be done, Ive done some art on my boards and as long as its clearcoated It rarely chips or anything