OK, to help others, here is the problem I found causing this and the solution.

I removed the EGR valve and it was very sooty. The car would die after a warm-up at red lights even with the vacuum source to the EGR valve removed. I removed the EGR valve, tapped the openings in the cast iron intake and threaded in pipe plugs. No vacuum leak, no exhaust leak, no EGR valve. Appears as the car warmed up the EGR would leak more to the point the car would not idle.

The car continues to idle fine now and has more vacuum at idle than before. I did check vacuum, about 17 at idle. The timing was 8 degrees.