SUCCESS

I can claim little credit. After 3 days of changing bulbs, checking grounds, etc,. While Googling the problem I found the exact answer,.

The problem,in short, was that the right front directional (I had spent all my time on the rear). That is a multi filament bulb. The solder on the terminals had melted and the terminals were joined. Using my trusty pocket knife I cut out the excess solder between the terminals, re-installed the bulb, and voila, all as it should be.