[A26B]

Charlie,
I had the same problem. Two different recommended, "supposedly good" alignment shops. Car was just not right. I put the ZR-1 up on my 4 post lift & used a couple of good, straight 2x4's to check alignment of front/rear alignment. Answer was obviously not correct. Rear camber, front alignment, front camber & toe all needed adjustment. I thought I must be doing something wrong.
So, I proceeded to do what I thought it needed, thinking it couldn't be any worse. The result of my shadetree/2x4 alignment turned out to really stabilize it. I never took it to another shop. Probably not as good as it should be, but I never experienced any abnormal tire wear or handling issues. Go figure, fancy machines w/questionable techs vs 2x4's & bubble level & tape measure.