2000 explorer rear end in a 98 gt?

[atlblue98gt]

Im planning on getting a complete rear end out of a 2000 explorer. It comes with 3.73 gears, posi, 31 spline axles, disk brakes with calipers. What all can I use for my set up? How hard would it be to mount that whole housing? I keep on breaking 28 spline. Already broke 2 superiors. And wanna go 31 spline. are the explorer axles longer, and if so by how much? Thanks

If I cant get this. I def wanna go the cheapest 31 spline swap.