With the radio wire harness where you can get to use a light probe to find a wire with power to it, ignition key off. That will be the always hot wire that is used to power the memory that remembers stations when the radio is off, it should be yellow. Make note of which wire that is. Then with the key on probe the connector again for a second hot wire, it should be red. That will be the one I would think you would want to use to power your CD player
For a new or rebuilt oil pump for your 1988 Chevy Celebrity 2.5L check with an automobile parts store.
it will be mounted at the harmonic balancer on the bottom and front of the engine
To adjust the valves on a Chevy Celebrity 2.5L 4 cylinder engine I would recommend that you consult a manual, either factory or Chilton or Haynes. There you will find not only how to do the adjustment but the settings to use to adjust the valves in the correct closed position.
You can find the wiring diagrams for a Chevy Celebrity in either a factory service manual or either a Chilton or Haynes manual.
Looking in my factory service manual for a 1989 Chevy Celebrity I found no reference to an accessory relay.
You can find a fuel line diagram for a 1988 Chevy Cheyenne in the vehicle's owner's manual. You can also find it at various auto stores.
There is no way to show you a fuse block here. The fuse block is on the bottom of the dash to the right of the steering column. You can find a diagram of it in one of the repair manuals such as Chilton or Haynes.
Some of the easiest sights that you can find 1988 Chevy parts will be craigslist, and ebay, you can also check the local car dismantlers shops and see if they have anything.
Prices tend to vary with suppliers, there does not seem to be a standard price. When I need parts for my Chevy Celebrity I survey the local sources and buy the best deal I find.
Looking in my 1989 Chevy Celebrity manual I find a park relay inside the wiper motor but no reference to an external wiper relay. There is a fuse on the fuse block.
I presume you are asking about the coolant reservoir on your Chevy Celebrity. There are several possibilities where you might be able to get one. You could try your local Chevrolet dealer, they might have a brand new one. You could look on eBay, items of that nature come up there on occasion. I would look in a local wrecking yard, you would have a good chance of getting one there.
On some cars there is a sticker in the engine compartment with a belt diagram.