Prototype planning for my Amp in a box "solution"

I believe I have picked out two of the circuits which I'd like to serve as channels for my "Amp in a box Solution".  The Thunderbird and the Brittania from Runoffgroove as provided by 1776 Effects.

I accidentally ordered a large Hammond Enclosure, but would like to test out the functionality and placement of the effects.

A while back i purchased a plastic enclosure from radioshack and i'm thinking of using it as a testing box of sorts. I thought I read something about having a grounding issue with it on Beavis Audio a while back, but since it has been taken down I can't see it.  I have the templates ready to drill the box, but I still think I need to do a bit more planning.