I may have found my answer. Lesonal has a product called "base fix" which is formulated for, quote "A clear insulating coat on sanded through areas (method for sanded through areas on second repair)"---- I will persue this product, which is fortunately sold by the quart, with my paint sales rep this week----Salvation may be in sight.---Actually, up to this point in my painting I haven't been held up by any of these paint shenanigans--its just got me worried as Hell. All I have left to do is finish paint the body (minus doors) and the 2 front fenders and splash aprons, then fix the screwed up grillshell and tailgate.