IMHO, you're talking about something here which could potentially cause serious injury if this "homebrew" controller should fail.
Jps, do yourself and your friend a big favor...check around in your area for a true electronics store
(not Fry's or Radio Shack) and talk to the counter guys. Bring the control boards in with you. A lot of those folks are quite sharp and can get you the parts or maybe even repair the problem for you at a reasonable cost.
And email Joe, he's on the right track!
Best of luck and feel free to email me if you need more help, I have a local e-store with the right people too.