[Jeff Higgins]

It strikes me that nothing you have done specifically addresses any differences in hot vs cold running. In other words, if any of these various hoses were indeed clogged or partially clogged, it would affect both hot and cold running. It's good that you have gotten these issues addressed, but they are clearly not the source of the problem.

Perhaps it is time to look somewhere else, like maybe ignition. Is the coil changing internal resistance as it heats up? The CDI box has already been suggested - maybe you should check it out. I noticed you said you are still running points - I would strongly suggest you replace them with one of the various electronic triggering devices, like the Pertronix. It's impossible to buy decent point anymore, made of proper, quality materials. I don't care what brand you are buying - there just isn't a big enough market anymore to entice the manufacturers to supply it with a quality product.

At the end of the day, you are still looking for something that changes as the car warms up, then "resets" when it is allowed to cool, even briefly. None of the plumbing/venting you have been working on fits that description. Start looking for something that does.