Can't shake vapor lock issue!

After it is warm and acting up, try starting it and manually closing the choke to see if it makes a difference. If it does, rev the way up then close the choke all the way until it dies. Sometimes that will suck junk out of the idle circuit. You can also try pulling the idle enrichment screws out and gently blow come compressed air into the holes.
Also look in the distrubutor and make sure the weights aren't sticking advanced when it gets warm.