I'm not sure, since I have the 60W mono head. On your speaker outs, is the left one labeled 'mono' or not?
Neither side is labeled mono. They are simply named right and left. I cant imagine that the amp cant be run in mono. I dont really want to rewire my cab right now as I will be getting a stereo cab in the next month or so but I dont want to blow the head. It doesnt say anything in the manual about running in mono either. Unless i missed something. I sat down and read the manual earlier today. I guess I may have to reread.