i figured it out you have to remove the still plates by the drivers seat on the floor, then you have to remove the rear seat and seat belts , then pry the trim off or interior panel starting by the side closest to the drivers door and work your way inward installation opposite of removal
for the 3rd door rear remove the trim around the interior handle , then unscrew the 2 bolts in the cup holder and armrest then pry off the panel with a trim removal tool if you don't have a trim removal tool a flathead screwdriver works too but you have to be extra careful with the screwdriver so as not to damage or break the trim panel. installation reverse of removal.
I have a 1999 gmc 1500 sierra,need to replace door pins and bushings.door sagging.
You put it where it belongs
The spare tire lowering handle is probably located under the rear seat on the 1999 GMC Sierra, if the vehicle is an extended cab. If it is not the extended cab, look behind the driver's seat for the handle.
1988-1999 Chevy and GMC full size the door speakers are six and a half inch on the extended cab the pillar speakers are 4x6 in. Some Silverados also had a small tweeter inside the door.
Remove the inner door panel.See link below.
The rear springs may be slightly heavier for a greater payload. Josh C.
My advice based on experience is to replace the entire hinge assembly.
The oxygen sensor on the 1999 Oldsmobile Cutlass Sierra is located on the lower exhaust. If you need to replace it, they are available for about $20 online.
Sierra Sciences was created in 1999.
Remove door panel, remove 4 screws, remove speaker, put new speaker in, replace screws, replace door panel. Done.
Replace the brake line, bleed the brake. top up with brake fluid. Done.
An individual SHOULD NOT replace an airbag. This should be done at the dealership only. There are both technical and physical dangers to replacing an airbag and individuals should not attempt such a job.