I would cover the edges of the wooden box with foam too, just in case you miscalculate and hit the side. for the foam just go on craigslist and anywhere you see there's a free couch sitting on some corner, go and snag the cushions. then cut them up
I've got a few glow-in-the-dark ones a friend gave to me that I really want to try. I think I'll throw one on without telling her, swing my dick around and start making light-saber noises.