Thats good, if the pinion seal was leaking it would throw oil on the under carriage including the exhaust and leak on the ground when parked. The part number for the seal is 8516N in National brand.
Thanks for the info. Do you know the mopar # of that seal? I had several NOS parts come with the car, so I may already have the seal. I probably wouldn't attempt to replace it even though I'm sure it's not that hard to do if you know what your doing. I've never even had a rear diff cover off on a car I've owned, let alone worked inside it. I leave that stuff to my mechanic. I will grab that $10 seal though. Will keep it around for a rainy day.