There is only one exchange unit part number for subject instrument cluster. When ordering an exchange unit from a service center, you must not only call out the part number 25078338, but specify whether vehicle has a six or eight cylinder engine.
The Service Center requires this information in order to 'Program' the exchange cluster for the intended application prior to shipment.
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.