I purchased another mustang to keep on hand as a spare and with that came a built 8.8 solid axle. It had Moser 31 Spline axles, moser spool, c-clip eliminators and 3:73 gears. Since I already have a solid axle and most of the components in this one would be of no use to me on a road course I decided to swap it with someone for an IRS. I found an owner of an 04 Cobra locally that was into drag racing so we swapped.

The swap is pretty straight forward for 99-04 models, SN95's and Fox Bodies will require a little more work. Tom Beverly and Lewis Tanner have a great guide on how to make it work. Installing it into an 02 GT, the only thing that threw us was the driveshaft. There are a few options here, some people have swapped u-joints and driveshaft tails but this requires buying parts. It was late so we decided it would be eaiser to just swap diff tails. A complete list of parts that needs to be swapped is below. Since the rear I was trading had a spool and c-clip eliminators the cobra owner will be unable to use ABS, but if you are swapping for a stock rear and the car originally came with ABS you can use the GT's abs sensors on the cobra and vise/versa. Some of the swap articles on the 'net claimed you needed to swap E-Brake cables as well. We found this to be untrue and the length of the two cables are almost identical.

Parts needed in swap,

From Both

• Differential Tail Shaft (Pinion Flange) 3 Jaw puller required.
• Rubber Brake Lines (swap these quickly so you don't loose to much fluid)
Shocks
Springs
ABS Sensors
Cat Back Exhaust
Rotors

From Solid Rear

• LCA's
• UCA's
• Pinion Snubber (the big rubber bump stop)
• Quad Shocks/Mounts (not needed w/ aftermarket control arms)

From IRS

• Entire IRS housing
• Rear IRS Mounts (where the quad shocks bolt on the solid rear)

When looking for an IRS to trade you may be interested in the differences between the various models, I have a tech page that outlines the differences. Basically, you want to find an 03/04 IRS and you should never pay more for a 99/01 IRS than you would an 03/04.