So after lots of thought and research on the differential I decided on the 31 spline Ford traction lok. I know people love the truetrac and I can't disagree that it is a great diff but it's also hard to argue against the probably millions of traction loks on the street and a lot of guys on other forums love them and swear by them. I talked to 2 different guys at work that drive their cars in the same manner as me with the traction lok and have no complaints. After I went through the list of some of the cars that have the exact diff with the carbon fiber disc I figured it will work perfect for me. This was not an easy decision but I feel like the best fit for me and yes cost had a small part but not much, the FRPP shipped to the door with taxes was $532 the truetrac with install kit and Ford gear shipped to door with taxes would be $1102. Here is what is included ( copy and pasted from Ford) and a few pictures of the stuff from the FRPP package. I also stayed with the 3.73 gear.
•Entire Kit is ALL Genuine Ford Racing
FRPP M-4204-F318C Traction Lok Differential
•Fits ALL 8.8 differentials with a 31 Spline Axles
•Will accept anti-lock exciter ring,
•Traction-Lok limited-slip differential
•Fits Solid or (IRS) independent rear suspension
•Includes Carbon Fiber Clutch Plates for increased durability
•Original equipment in 2003-04 Mustang Cobra
•Requires 4-ounces of CM-19546-A1 friction modifier with initial fill
FRPP M-4209-88373 Ring & Pinion Gears
• Includes Ford Pinion Nut
• Includes Ford Crush Sleeve
• Made by Ford Racing
•No one does 8.8" gears better than Ford Racing...stonger and quieter.
•The 8.8" rear end has been the standard in performance since its introduction in the Mustang in 1986 and Ford Racing is the manufacturer of choice when it's time to hop-up your axle.
•Made in the United States at Ford's Sterling Axle Plant (competitors in this price range are primarily produced in China)
•OEM quality - our superior surface finish, hardening, and manufacturing consistency provide the strongest and quietest 8.8" gears in the market! These are the same units that have 100,000 mile warranties in our production cars. Higher quality gears means more satisfied customers!
•Race Proven - Ford Racing 8.8" gears are the choice of championship road racing and drag racing teams including Multimatic Motorsports and Kurgan Motorsports.
FRPP M-4210-B2 Ring & Pinion Installation Kit
• Excellent upgrade for all 8.8" rear ends through 2014. Does not fit 2015+
• High-torque bearing gives added durability for modified vehicles
• Contains all components from M-4210-A plus all differential bearings
-2012 Shelby GT500 high-torque pinion bearing
-Pinion and carrier shims
-Ring gear bolts
-Mustang GT carrier bearings