When timing a diesel engine with the timing meter, you have been instructed to disconnect the two wire connector at the alternator so that it does not charge. Due to the relocation of this connector on 1984 models equipped with a diesel engine and air conditioning, it is difficult to remove. If you remove the gage fuse when the engine is not running, the alternator will not charge. Either method is satisfactory.
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.