Some of the rear suspension parts were lying around the shop.
That is the 9 inch rear end that comes standard with the kit in the picture with the IRS parts
This has a limited slip with a 2.75 to 1 rear end inside. I needed to go to a real tall gear because 5th in the Richmond is 1 to 1.
Something that makes this rear assembly really cool it that it can be dropped out of the car relitively quickly. You can also buy the car with the live axle and switch to the IRS after the fact at any time. It is all Ford parts.