The impossible to solve overheating problem

mvh said
You said you adjusted the ignition from "very rich to lean" -- that doesn't make sense. The ignition controls advance and retard -- the carburetor controls rich to lean. So what exactly did you adjust?

Both extreme advance and extreme retard conditions can cause overheating, for different reasons to do with poor combustion.

That electric fan is large diameter but it doesn't cover a lot of the radiator (looks like less than 50%). Most set-ups use two slightly smaller fans for a wide radiator like that. Have you tried it with the stock engine-driven fan and no shroud?

Does the timing not affect the O2 in the exhaust at all? I.e rich/lean?
Anyway, I adjusted the advance and retard to pretty extreme in either direction just to see that my timing mark wasnt off or something but it made no difference so I set the timing to where the engine runs best. The carb is adjusted correctly with respect to rich lean.
The car came with an engine driven fan without a shrowd which I have tried since this problem started again yes. Thing is both set ups have worked old and new.