8 3/4 third member suregrip 3.91

I have a 8 3/4 third member sure grip posi that has 3.91 gears. It is completely rebuilt with no miles on it. It has a 657 case, which is the older case, but just as durable. This chunk was rebuilt and put into a 66 coronet that was set up for drag. Unfortunately, the car never made it to the track, and got parted out. I am asking $500 for it. Will ship if needed. Let's make a deal. Pm me if interested.