Thanks for the responses
Gaz64; F2, F16- leaner low throttle response than F11?
13; Oh yes, jets cleaned and seated many, many times. Amazing what happens when a fleck of tiny debris finds itself in one idle jet.
big deuce; chokes are 36
Caprimaniac; plugs look really good, medium grey with midwestern fuel. Will check them as you stated. AFR sensors are located just after header collector. FAST meter, do not know about calibrating, will read up. Timing is 36 deg @ 2800 rpm, 20 deg initial. Was that IDF tuning pdf on a GT40? if so, his major issue was linkage. I had the same problems with loose linkage arms, which have been corrected.
zimmy; have not messed with the squirter size, but have gone up in pump bypass size. In my case, less pump fuel, better results. I am at 65 bypass now.