I just measured both rears (by myself)
stock 37 was about 59" -@ wheel mounting surfaces
and the explorer 8.8 was about 59" 1/2" @ wheel mounting surfaces
(I was wrong in the previous post about the difference, its only about a 1/2")
so they are very close in width
they come in a 3.08 ratio, but if you are using an overdrive trans, I would go with a little lower gears
maybe 3.27, 3.55, or even 3.73
here is a good
link to a site with some info on the 8.8 rears there is also some good info here if you use the search
maybe someone else can chime in, about some other choices on a rearend and/or gearing choices