Rear subframe collapse is pretty common in 30-yr-old Panteras; if you're running stiff shock/springs, the front ride height could be affected. Putting the thing up on a lift will tell you if there's collision damage to the front. If none is visible, it's probably the rear subframe. You may need to take the car to a frame shop to have things straightened, or by adding adjustable spring perch shocks and an adjustable rear stress bar, you might be able to do it yourself. Many Panteras have had a VERY hard life and without seeing it, no real diagnosis can be had. If you're East Coast, take it to one of the knowlegable POCA guys out there to check it out.
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