Hello Typhoon
I was cleaning up my hard drive and came upon your old post about a 12 genset. While it's been a long time now, I wanted to let you know(in case anyone else is asking you) that Dixie Alternators in Canada (also has presence in US) makes some whopping big alternators. I put together a 325A unit driven by a Kubota 2 cylinder (~12hp). Can't run full field or the Kubota lugs to near death. But can hold an honest 300A into our AGM's.
Custom work available, just have to wait a bit for the construction.
Doug