What Little I Know
You can get some things from
Galls. It's mostly for emergency personnel, but the push bar they offer is better than none. And their center console kit gives you more switch positions and accessory mounts than you'll ever need.
The Gen2's high-tech RSC program might not play well with locking diffs, so I'd steer clear from those. I've been researching it for my own use, and am going with the
Torsen T-2 gear type LSD. I've never heard of it being used in an Explorer, but it's used in the Ranger with more or less the same RSC program.
Note that the T-2 has different versions. You want the 31-spline IRS version. So don't plan on getting a junkyard part from an old Ranger. You can get yours front and rear from the Ford Racing catalog. There's also a T-2R variant that you might be able to use on the rear end, that offers preload for more torque bias. Not that you'll really need it, since the traction control will slow a spinning wheel for you.
I wouldn't use any more tire than was absolutely necessary. Not unless you can find someone to fab stronger suspension parts for you. This really wasn't meant to be a rock crawler, so if that's what you're hoping for, you might want to start with a truck with more aftermarket support.