Ive never tackled one in a van (I try to avoid vans at all costs) but Ive done several on full sized pick ups and smaller S trucks as they have the same pump.
A couple of the bolts on the pump are a huge PIA to get to.
You'll also need a special "puller" for the pulley. You can NOT use an old style 3 jaw puller that grabs around the perimeter of the pulley as it will just mangle it. You will need one that has the "clamb shell" apparatus that grabs the slot around the center hub of the pulley. You can pick one up at about any chain auto parts store for ~$40 that includes the correct attachments. Dont waste your time on the cheaper puller that they offer that is made to fit only the late model GM stuff. Its too cheap and will break almost immediately (BTDT).
To reinstall the pully once the new pump is on I put the pulley out in the sun or heat it with a halogen lamp. This will allow the pulley to slip right on and when its cool it'll be plenty tight.
Fill with PS fluid and fire up the engine and start turning the steering wheel lock to lock and checking for proper fluid level/adding fluid. The pump will howl and make some racket until the air is worked out but thats normal.
Youre a braver soul than me doing one on a van as its a PIA to do in a full sized pick up where there is plenty of room to work. You'll prolly invent a few new four letter words and need several cold ones to keep your sanity.
HTH
