Chevrolet Dealer Service Bulletin 88-20 is being reissued to change the retention procedure and labor operation for rear speakers. All copies of 88-20 (Section 9) dated May, 1987 should be destroyed.
Some vehicles have had rear speaker assemblies falling off of their mountings on the rear compartment shelf. This occurs when the tabs on the speaker assembly come out of their slats in the rear seat to the back window panel.
To repair this condition install an I/P trim plate clip, PIN 25510099, on each of the speaker enclosure tabs and reinstall the assembly (see illustration).
Labor Operation Number: T1246 Labor Time: .2 Hour
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.