I pulled the plenum off today and took a look at the regulator. From the passenger side, which is where I was at when I put it on, everything looked good. When I went around to the drivers side the retaining clip wasn't completely over the tab and was spread open far enough to let the regulator back out on that side. It cost me another gasket set and oil change for not double checking that in the first place. I greatly appreciate all of your input !! At least I cut two hours off my plenum removal/install this time ! Many thanks. Dale