I actually use a *very* weak solution of the Clorox Clean-Up stuff. It's meant to be used as-is, but I put a couple capfuls in a spray bottle and spray the viv down with that. I wipe it with paper towels, then rinse it with fresh water. I also fill up the container with clean water and let it sit for a half an hour or so. Then I dump that out and rinse again.
This is pretty much the same procedure I've used for roughly 8 years when I have to completely "break down" a fishtank (meaning I'm starting a completely new tank). I haven't had any problems with the fish, so I assume it's okay for the snakes.
I actually think Hypancistrus' idea of using some declorinator in the rinse might be a good idea. After reading that, I think I'll add it to my routine as an extra safety measure.