I know you want to figure it out just like I would, but after all that work, I would put on another Rochester. No use getting frustrated, move on to something else and figure it out later. It will also give you something to compare and study the difference you see. Then you will find the problem. hd4unm has good thoughts. It is also possible that you run out of gas in the bowl after your "test pumps" and there is a problem with fuel delivery to carb. Fuel pump, dirty filter, clog somewhere, unvented tank? you may want to do a test for that. Take off line at carb, turn engine over and see if it fills a cup pretty fast. It will pulse, splatter and probably start a small fire, so be careful.
Unhook the main, center distributor wire so no spark. Carbking will know.
