Guild Masteramp, old Tweed amp, anyone know which model?

[hearforever]

I'm trying to fix up an old tweed Guild "Masteramp" for a friend but I haven't been able to find anything about it online. It looks similar to other Masteramp models I have found but not similar enough. The tubes from L-R are 12AT7, 12AT7, 6J5, 6SN7, 6V6 and 5Y3
It's got a 12" alnico speaker. I'm not convinced these are the right tubes for the amp. My friend bought it on Ebay as "not working"– the power cord is totally dried up and a lot of coupling caps look like they've seen better days. I imagine the filter caps need replacing, too.

I'm not exactly excited about the prospect of tracing the schematic by hand since its such a birds nest and a lot of wiring in a tight chassis...was hoping someone else might know a bit about this thing

[überfuzz]

I kind of sympathise with 'I'm not exactly excited...'. Why perchase an amp in this state if he can't fix it. Tell him to get the schematics, then you'll have a look.