That is some great information. I had also heard it was a mix, but I heard Marshall/5150/Bogner. But I have a Marshall JVM and a Hellwin, and I don't think they sound similar, other than both being high gain. But this new information directly from James Brown clears things up. Very interesting!
VERY long story short, I had an issue with my Hellwin, and had taken it to my local amp builder/technician, and he eventually found the Schecter "Hellwin technician guy" that was supposed to service them, and I am now in possession of the schematics for the Hellwin (which have the Kustom brand on the drawing title blocks, by the way - that didn't make sense to me at first, but it does now!). I don't have any experience building amps, but it had crossed my mind to try to learn something and then attempt to build a lower wattage combo version. If anyone has a Hellwin, and would like the schematics just in case you need work done on it or something, you can message me and I can try to send them to you.