I am an idiot.
Last night I was going to remove the WUR to send back to Flowtech, and I started to think about anything else that could be the problem. I have not checked the timing since I got car back from engine rebuild. Went for a drive to warm it up and checked timing. 5 degrees ATDC
I reset @ 5 BTDC reset idle to 900 and went for ride to listen for pinging etc.... car ran great. (I am amazed how well it ran with retarded timing before) My timing light hates the MSD ignition and gets erratic at high rpms so I could not accurately test total timing advance, but I had this dizzy rebuilt by Barry Hershon and I know that it tops out at 32 when set at 5BTDC. (distributor is now 100% mechanical advance)
Did a cold start today (65f) and car had no rpm drop, no surge, no bad behavior at all. RPMs immediately went to 1600 and slowly dropped to 900. I will do a cold start again tomorrow am to verify, but I think I found the problem. I feel real stupid but I hope someone else can learn from this thread. Don't assume anything. Check basics 1st. etc....... Again thanks to all that have assisted!!!