Get the yoke off of an earlier Explorer with drum brakes - those had 1310 U-joints. The 1330 u-joint came with the disc brake 8.8s.
To answer your other questions:
At my local pull a part, they will charge you for all the extra components - rotors, calipers, yoke, e brake cables, etc. If yours is the same, then be sure to just get what you need or plan to reuse.
Calipers and rotors are optional - you might want to replace them. Or get rotors calipers from another Explorer and swap them onto your axle, if yours aren't good.
Figure out how you want to do your hard brake lines. You may want to grab an extra Explorer passenger side brake line while you are there. (research, and this will be clear)
Yes, you may want to grab the e brake cables as suggested above. I cut the cable well forward up near the front door with a hacksaw blade and removed a bracket to get the e brake cable free. I got them, but didn't use them - see the details in my 8.8 thread in my signature.
Also, a special tool will make e brake cable work MUCH easier. Grab "Lisle 40750" from your local parts store.
If you remove the calipers, make sure that that you keep the banjo bolts - they seem to be difficult to find. Also, keep the little thin steel tracks that the pads run on - they fall off and get lost very easily. And of course, also keep the caliper mounting bolts.