Wait, I just noticed you said GCX system. You'd have to contact Voodoo Labs about that. I thought you said you had an RJM Amp Gizmo. Basically, either one will work. Also you can e-mail Voodoo Labs, they're alright about getting back to e-mail, but good luck getting anyone on the phone
I'm not entirely too sure if you have to order them through a dealer or not. Go here RJM Music Technology, Inc. - Creators of the RG-16, Amp Gizmo and other MIDI switching systems and e-mail their sales guys and see if they'll make the cable for the UL for you and ship it to you direct.
Thanks for the advice there Yeah, i really look forward to it, assuming i can search out a teacher here If not, i may have to do something like German until i go back to Melbourne (more teachers). I'll let you know tho