Changed my mind on the Bondo – I would probably screw up a putty compound, get it places I don’t want it, and screw the whole thing up in ways that would be nearly irreversible.
My first thought was thin styrene sheets cut to size and glued over the Nerf logo. This would make a gap between the body of the gun and the styrene panel, but I don’t think it would actually look too bad. Unfortunately, I remembered the other markings – “Warning: Don’t use this toy as a weapon of mass destruction” and so on that the cover up method wouldn’t work on.
Luck set in and a friend of mine has offered to let me use his Dremel. I’d like to just have one myself, but I’m not in the mood to part with the money on something that I’m not certain I’ll be using again anytime in the next two years. I may have to buy my own sanding attachment, but that’s considerably cheaper than the tool itself. This should let me quickly (and perhaps more importantly, accurately) remove the markings.