GM Service Manual Online
For 1990-2009 cars only
Figure 1:

Rear Axle Shift Relay - Two Speed to Crossmember (HPZ)


Object Number: 220258  Size: MF
(1)Rear Axle Shift Relay - Two Speed (HPZ)
Figure 2:

Two-Speed Rear Axle Harness to Frame (HPZ)


Object Number: 216360  Size: MF
(1)Rear Axle Shift Motor - Two Speed (HPZ)
(2)Rear Axle Shift Relay - Two Speed (HPZ)
Figure 3:

Two-Speed Rear Axle Harness to Frame (HR1/HR2)


Object Number: 216347  Size: MF
(1)Rear Axle Air Shift Switch - Two Speed
Figure 4:

Rear Axle Shift Relay - Two Speed (HPZ)


Object Number: 216359  Size: MF
(1)Rear Axle Shift Relay - Two Speed (HPZ)
Figure 5:

Rear Axle Air Shift Switch - Two Speed (HR1/HR2)


Object Number: 216348  Size: MF
(1)Rear Axle Air Shift Switch - Two Speed