Can anybody solve this hot start issue? I'm out of ideas!

One thing I've been wanting to try is a water heated carb spacer, like Ferds used to use, like this:



The coolant SHOULD be cooler than the intake, unless possibly you are running an air gap. I bought a couple off ebay, one of which seems to be completely plugged!!! And "they" require a little work because of the construction underneath, IE sealing problems. So I have not yet got one "on there."