The steering gear box will eventually wear out and have slack min it like anything else. You can also check the tie-rods under the front. They wear out pretty fast. Have someone move the steering wheel back and forth while you crawl under the front end and watch the linkage. if a tie rod moves and the rod it's connected to doesn't move as much, it's bad. There should be no slack in the steering linkage.
This is not an easy task. Get a factory shop manual from AUTOBOOKSONLINE.COM . It is about the only book with steering column information like what you need.
Check in either a Chilton or Haynes manual. Your local library may have one if you don't have one.
Yes
steering colm for 1989chev silverado
yes
All Chevy Celebrities have rack and pinion steering.
You can find fuse block diagrams for your 1989 Chevy Celebrity in either a factory service manual, Chilton manual or Haynes manual. If you don't have a manual your local library may have a Chilton or Haynes.
How to change the power steering pump depends on which engine your car has.
getrag
Left of the steering column, under the dashboard.
you will need a power steering pulley puller other than that its gravy
According to my factory service manual the horn relay for a 1989 Chevy Celebrity is located in the "convenience center" which is behind the instrument panel on the left side of the steering wheel. To replace the relay one would simply pull out the old relay and plug in the new relay.