Should erratic tachometer operation be encountered on 1978-86 Cutlass Supreme models, the tachometer contact (shorting adapter) should be checked for proper electrical contact. The lock ears of the tachometer contact (shorting adapter) should be fully engaged and the contact should be soldered to the circuit board to enhance the electrical contact.
Before soldering contacts be sure to note position of tachometer contact (shorting adapter) for engine application.
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.