You don't, you replace it.
axel hub nut is 30 mm
185 to 260 ft lbs this is the front center nut that holds axle and front wheel bearing together not wheel lug nuts
in the axle
chilton's
Over the rear axle
Should be a 35mm.
That switch is screewed into the top of the transfur case that's bolted to the rear of the transmission.
Under the motor running parallel to the front axle. It is round about the size of a small coffee can.
147 foot pounds
You can find a 1989 Chevy front axle diagram at most Chevrolet dealerships. Most local libraries will have Chevrolet service manuals with the front axle diagram.
It is located right above the rear axle.
Usually underneath near the back axle.