[bobcowan]

No, the Mustang IRS is not a bolt in operation. It can be done with a few mods, though. The FFR kit is designed to use IRS parts from a Thunderbird Super Coupe. Thjose parts are similar to the mustang, but there are some important differances.

Is your kit set up for an IRS? If it is, the supporting frame work has been welded in. If it isn't, you'll need to get the kit from FFR and weld the frame in yourself.