I have already purchased 4.10 gears for my 2003 Mach 1 and I am waiting until I get the rest of my rear-end components to have it installed. In addition to the gears here is what I plan on adding to the rear:
1.) Moser 31 spline forged axles
2.) FRPP 31 spline limited slip differential
Ford Racing 4.10's for 8.8, brand new in the box. They came with a car I bought, and I dont need them. Includes shims. $125 SHIPPED
Ford M-4210-C Gear Install Kit, $100 new, sell for $80 shipped, still brand new in the box as well! (not pictured)
Or $195 SHIPPED for everything!