750 aed stumble off idle/start

Simple test.

Get car warmed up, twist distributor a bit CCW, if the engine picked up RPM it wants the timing at idle. Reset idle speed and do it again. Find the max point that the car still starts when hot without dragging badly or kicking back.

As someone else said... TIMING FIRST!!!!

Once you get that sorted out, your entire carb tuning set up will change.