1992 rear-end, etc.

[abebesheir]

As I mentioned before... I recently bought a 1992 9c1 for $500. It was on eBay for $550 or best offer and I was surprised no one bought it. Now I am learning why.
The guy I got it from told me that the pinion bearings needed to be replaced as it made a howling sound while driving at a certain speed (above 20 and below 70). I did some online research and found that the problem is a worn ring and pinion.
I need to get this car registered and through inspections soon as it's sitting in my front yard and soon to be without plates (I drove it back from New Hampshire with the previous owner's plates).
What are my options?
Thanks for any replies and I apologize if any of my previous comments on this subject seem a little uneducated... I am learning about this as I go along.