I'm thinking of using Audio F/X since the owner and a lot of the employees are really cool. Plus they don't care what people think.

(as opposed to the other store that has expressed interest in letting me do this, they are an "official" supplier of Monster Cable and act, well, rather pushy).
http://www.audiofx.com/intro4.htm
I'll talk to the owner about how best to set this up. I'm thinking after closeing hours would work the best.