Now that the 9" Ford has been mentioned I guess it's safe to point out another FoMoCo differential that is both readily available, is 60" wide from mounting surface to mounting surface, has 31 spline axles, most are 3.73, are available in both big drum and also disc brakes, are positraction and can be had for around $100.00.
These are found in the 94 Explorers (drum) and the 95+ (disc). They also have a slight offset which does NOT effect balance and the emergency brake setup controls both sides with one cable. In addition, the axle codes (D5, D7) are on the sticker on the drivers door. The vast majority of V6 Explorers use a .63 OD transmission and the 3.73 posi diff is the standard fair.
Personally, I think the 8.8", with the 31 spline axles is nearly as tough as the 9" and aside from having a 5 on 4-1/2" bolt pattern would be a good option. I've been running one behind a built 5 speed 355 SBC in my Retro Hot Rod and think it's a great diff for the money. Have pics of the diff and install in my Webshots Hot Rod album.
If you go this direction be sure to get the U-bolts and the bottom plate as the axle tubes are 3-1/4" diameter.
Dave
