Sorry for the lack of update here. I tried the square transfer slot setting with vacuum advance disconnected. It still idled at 3000. So, I turned it down to the appropriate idle speed. In discussions, it was determined that the fast mechanical ramp plus the manifold vacuum was too much. I removed the vacuum entirely. Just mechanical advance. 18⁰ ar idle and 36⁰ all in at 2200. I also added a 0.136 air bleed to each carb. All problems gone and got 11mpg on a 7hr cruise. It works amazing.