The control arm on a Grumman Long Life Vehicle, or LLV, postal truck (used by the United States Postal Service (USPS)) is exactly the same as the control arm on the Chevrolet S-10 pickup truck, so the replacement procedure is almost identical. This video will show you that procedure, but it's important that you get the right part for the side you're replacing. The LLV is right-side steering, so the driver's side is the passenger's side on the S-10. It's a little confusing, so be careful.
* GM Part # 12376266 (driver's side)
* GM Part # 12376265 (passenger's side)
* GM Part # 1362014 (rubber bumper part)