OK guys, looks like I am dealing with some real pros.
I've been looking at this problem for 9 months and no one has suggested the solutions offered by 67drake, davidpozzi and stevo camaro. But, on thinking about your solutions, you all sound like a solvtion to my problem.
"Drake," as the original owner of this machine, I just laid-in the rear springs last week after replacing the bushings. So I really don't want to hear about a "worn rear." Unfortunately for me, the original rear single leaf springs were not replace, only the bushings. But you may be right. On the other hand, I cant see how the rear springs would take any wear over the years, which is the primary reason I did not replace them. (Yes, other than I can't get original GMs, there were other reasons.)
However, it is possible that you are correct in that the front elevation is "the proper height." I never, nor has anyone else, thought about this perspective.
But I realy think davidpossi and stevo camaro are cloese to the truth. Torquing the upper and lower control arms and the upper control arm shaft bushing nut sound the most promising source of the problem. These were done while they were "hanging" in the air withour any engine or weight appiied and the wheels were not on the ground--nor were they even attached.
I plan on loosening the appropriate nuts as stevo camaro suggests, and then wathching the front end slowly and wonderfully sink to a "normal" height as specified in the Assembly Manual. And 67drake, hopefully this height will match the rear end.
Thanks a million guys!!!!!! A job well done. But, I have some more challenges to follow.