Thanks for all the help and info Joe!
I found the problem and yes it was the wide brand reduced to a narrow band signal that was causing the problem. I've changed the oxygen sensor back to a heated narrow band type and everything is working perfectly again! I'll keep one of the two widebands on the passenger exhaust to monitor the A/F ratio but it's looking very nice. After some driving I could set the dwell or 30 degrees. The A/F ratio under normal conditions is around 14.3:1 (a hair rich) and under WOT conditions it's between 11.5:1 and 13.0:1. I could still tweak it a little by changing the secondairy rods and the butterfly spring tension but that is a nice thing to do on a summersday. Also setting up the choke just right is something on the list.
Greetings Peter