Finally dug into it and figured it out. Using a bike stand, I clamped the bike upside down, removed both shifter covers and placed it in the sun so I could really see what was going on. The spring & pivot were gunked up just enough to prevent the pawl from engaging the shifter cog.
Using LPS #1, I directed the spray right where the problem was, let it sit for about 5 min. then blasted it clean with an air compressor. Then repeated. Cleaned the front shifter out while I was at it. Then lubricated all the moving joints, and cables.
Went for a ride. Nice....rear shifter worked fine. Nice to have all my gears back, especially on the hills and after laying off the Summer (just too hot). I'm paying for it now though getting back in shape.....