Can a Ford 8.8 handle a big block?

If you still have the explorer, there is an axle code on the drivers door. If the axle code starts with a D or L, it is a limited slip. If the code is just a 2 digit number (usually 41, 42, 43, 45, or 46) then it is an open diff. If you have the rear only, if you jack it up and turn the wheel, the other wheel turns the same direction on a limited slip, opposite direction on an open diff.
Also, if you are looking for the housing to hold up, have a professional welder, weld the axle tubes to the center housing with a low-hydrogen rod. And get a rear diff cover that has girdle support for the caps.