There are a few different ways to do this, but obviously the starting point is the passenger-side mounted 3G alternator and bracket from a '92 - '94 2.3 Ranger. This alternator (only) is shared with the 90's Explorer, so it's readily available in the junkyard or you'll likely find it on the shelf at any autoparts store. The Explorer 12V+ power cable is also the perfect length for use in the XR and it comes complete with an in-line dual fusible link.
Assumming you still want power steering, here's what you need:
Crank pulley donor:
'83 - '88 Ranger or '87/8 Turbo Coupe (you can also use a '89 - '91 Ranger or '91 - '93 Mustang, but these are DIS engines so you'll have to get the ring gear that the pulley bolts to. These can often be rust-seized to the crank, but if you're considering a future DIS conversion, it might be worth the effort)
Water pump pulley donor:
'83 - '91 Ranger or '87 - '93 Mustang (no difference on the DIS engines, so this should be the easiest one to find)
Power steering bracket/pulley/tensioner:
'87 - '90 Mustang (best choice)
'91 - '93 Mustang (nearly as good, but one bolt hole doesn't line up)
'87/8 Turbo Coupe
The belt for the alternator side is Dayco 5060407 or Duralast 407K6, although you can go +/- about an inch in either direction and the tensioner will take up the slack.
Not sure about the pwr steering side belt, as I'm not running one, but here's a pic of what it looks like (not my engine).