When removing the left exhaust manifold on a 1979-84 'E'or 'K' series vehicle equipped with a 5.7L diesel engine, the transmission shift linkage does not have to be removed or disconnected as described in the service manual, section 6.
The procedure should read as follows:
Remove or Disconnect
1. Heat shield 2. Exhaust pipe 3. Lower generator bracket (loosen only) 4. Exhaust manifold
Please correct your manuals accordingly.
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.