Tire and wheel match-mounting has been eliminated on all 1991 GM cars and trucks. This is possible because tires and wheels are now manufactured to very close tolerances, which essentially eliminates and "high" or "low" points.
A high point label or dot may still be on some tires, but it will not necessarily line up with the wheel's valve. Dealers should NOT dismount the tire to align this mark with the valve, as no improvement in tire/wheel match will occur.
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.