Not sure why the name calling. This is an obsolete item. The general G body enthusiast is pretty tight, budget builder and DIY'ers. That means you have no issues welding up and putting in a Mustang rear. Different width, converting to Ford brakes, 4.5" bolt pattern and getting the parking brake to work.
For a 34 year old part the term bolt in does not mean buy and bolt in. It means it will fit without modification. Rebuild is expected in any 30 year old mechanical part.
I had one for sale for $2300 Canadian. I was already told by the DIY'ers what a retard I am but I was not trying to put it in their garage. It was for someone who wanted a low mileage rust free
Grand National G80.
The bottom line is it was sold to a G body guy, not on these forums. He could not believe it was available and bought it sight unseen.
My conversation with him confirms my theory. There are 2 buyers out there for G body rears. 1 is you don't care what rear ends up in your car. It's basically is Dollars vs strength or availability.
2. Is someone looking for a factory correct rear. IMHO, there is no other option for them. Similar to Grand National front seats. The price is not what they are worth. The price is what you will need to pay someone because there are not many left. If that hurts your wallet. Standard Regal seats or you are sitting in a set of Procars.