Barry, I have some of the BW-65 developer, but haven't really tried it yet. Where do you get your Fuji MI-DUP film? Is it much the same as the Warehouse dupe film? Are all these x-ray dupe films pretty much the same or are some better than others?
Jeffrey, I did a little searching(thanks Google) and came up with cxsonline.com. They seem to have Fuji, Kodak and a CXS brand that is Agfa in 14x17, 10x12, and 8x10 Along with chemistry to process. It is not GBX chemistry, but I suspect it is very similar. I also found a place to get the GBX chemsitry for about the same price as the chemistry from CXS. Have you ever, or is it possible to machine process this film? I have a Fujimoto CP-51 color processor that I have used for color, b&w and graphic arts film with paper developer for a continuous tone image. The processor has an infinite adjustment in speed and temperature of chemistry.
I think that I am going to try the darkroom methods for enlarged negatives again and fully explore all the analogue ways before going over to the dark side Eventually I will probably have to go to digital negatives if I want to do full color Gum as that requires color separations and that is a lot easier with P***toS**p.