Test drove it today. Turned the vacuum regulator off, to get full power to the brakes, then went to full restrictive on the front brake proportioning valve (57% maximum restriction) which skids the rear first. Then backed off the proportioning valve one turn... it is close, but still too much rear brakes. Will try 1.5 turns next trip. Probably should reduce the vacuum in the power brakes too, as the brakes are too powerful.
The QA1 shocks were full of oil, and working correctly. Took the springs off, and could feel the resistance change as I adjusted them. Put them back on Mad Max, (my Goblin), and tried using the shock adjustment to stop wheel hopping under hard braking. Started at 0 clicks, got wheel hop. Went to 2 clicks, got wheel hop, slowly worked my way to 18 clicks (full out) and still got wheel hop. Ug. Still searching for the wheel hop issue. There are lots of Goblins running the 275mm Toyo Proxes R1R front tires, I don't think they are getting wheel hop under hard braking.