how much did the springs drop the rear? did the panhard bar make a big difference?
About 5/8 - 3/4 of an inch drop, the blower dropped the front a little so it worked out well. Main reason I like the Roush springs is the rear doesnt squat as bad, the stock springs are pretty soft and nailing the throttle at 40mph it would squat so bad I thought the tires were going to hit inside the wheelwell. Granted the ride is a bit stiffer but its not bad.
I just did the panhard to center the rear, with the stock tires you couldnt notice the rear was off but with the 285s you could really see one side sticking out further than the other. Only difference it made was a little more noise from the poly bushings. I'd prefer the stocker to be honest, if it was centered better.