No Chevy Celebrity ever had a 4.0L engine
Which engine does your car have?
How to change the power steering pump depends on which engine your car has.
The spark plug gap for your 1989 Chevy Celebrity 2.8 V6 is .045".
There is no 1994 Chevy Celebrity. The Celebrity was discontinued in 1989, with the exception of the station wagon which remained in production through 1990. Assuming you mean 1984, depending on which engine it is, very easy or slightly difficult.
The thermostat on a 1989 Chevy Celebrity is located under the water outlet fitting. Follow the upper radiator hose, it will end at the water outlet.
I found a site that listed the curb weight of a 1989 Chevy Celebrity at 3100 pounds. Of course that would vary depending on the engine and other options on a given car.
On a 1989 Chevy Celebrity the timing is controlled by the engine control module, there is no specification or provision for adjusting the timing manually.
On a 2.8l v6 it is at the front of the engine behind the ignition coils.
Pull the old fuse out and put the replacement fuse in.
On some cars there is a sticker in the engine compartment with a belt diagram.
To change the front blinker bulb on your 1989 Chevy Celebrity simply reach up behind the bumper and unplug the socket from the fixture. Replace the bulb in the socket and plug the socket back into the fixture.
According to one source I found the weight of a 1989 Chevy Celebrity varied between 2751 to 2928 pounds. Actual weight of a given car would depend on engine, transmission and other options.