Thanks to all with your replies.

Coupla points - Everything that was replaced and made no difference was not left in, so I am not throwing parts or $$$ at the problem.
My dealer mechanic and I are working through this and he has started to scratch his head regarding this and is talking with a few other "old timers" in the shop to cme up w/something.

I replaced all vacuum fittings and most vac lines awhile ago and must state that this made a HUGE difference in idle quality and increased MPG. A must for anyone that hasnt touched these things, only had about $40 and one afternoon tied up on that project.

I know the mechanic has evrything set at OEM specs, have watched him do most of the work. I feel really lucky that he has been so persistent with the problem. Methinks he is taking this as a personal challenge now!

Again thanks for the input. I'll let you all know how it comes out.