I went and picked up coil and spare distributor from a friend and installed the coil. I then decided to check the plug wires. And what did I find, a loose plug wire on the #3 cylinder, just sitting in the hole, probably making slight contact. I pushed it back on the plug, put my old coil back on (as I knew I found by problem) and it runs great (still at little popping when cold).
I did not adhere to the basic law of VW mechanics, start with the basics . The good news is, I now have really clean carbs that I know are free from any junk and adjusted correctly.
Thanks for your thoughts and ideas!
Chris