1992 Buick Century Replacing the powewr steering unit

Hello . thanks for the donation ..much appreciated ..

There are 2 types of pump fitted to your model .. have included diagram of both .. hope this helps

POWER STEERING PUMP PULLEY
Removal
Remove drive belt. It may be necessary to remove power steering pump for clearance (leave hoses connected to pump if possible). See POWER STEERING PUMP . Install Pulley Remover (J-25034-B) on pulley. While holding remover body with wrench, turn center bolt clockwise to draw pulley off shaft.
Installation
Using Pulley Installer (J-25033-B), press pulley onto shaft until face of pulley hub is even with end of shaft. DO NOT use a press to install pulley. If pump was removed, install pump. Fill and bleed hydraulic system. See HYDRAULIC SYSTEM BLEEDING under LUBRICATION.

POWER STEERING PUMP
Removal
Remove drive belt. Remove belt tensioner (if necessary). Remove pump pulley. See POWER STEERING PUMP PULLEY . Disconnect pressure line from pump. On vehicles with pump adaptor, disconnect return line from pump adaptor using Quick Connect Separator (J-36391). On all vehicles, remove mounting bolts. Remove pump adaptor (if equipped). Remove pump.
Installation
To install, reverse removal procedure. Fill and bleed hydraulic system.

I do not have any diagrams of the actual pulley in use i'm afraid. The outside legs of pulley remover go around the pulley. Locate centre bolt onto pump centre shaft, turn centre bolt of puller clockwise with a wrench to push down on pump shaft drawing the pulley off the pump shaft

Install Pulley Remover (J-25034-B) on pulley. While holding remover body with wrench, turn center bolt clockwise to draw pulley off shaft.