In the hopes of avoiding screaming fits within the model railroad world, I offer this piece of information.
After removing the shell of the model you will look for the screws which hold the engine weight onto the frame. The instructions call for the removal of the weight to get at the gear towers to apply lubrication. You will not see any screws that will enable you to remove the weight. They are there, but hidden from view. In order to make the separation you must unscrew the eight scews securing the two speakers. remove the speakers from their recesses. Then remove the rubberized gaskets under the speakers. This will expose the four screws holding the weight to the frame. The front gear tower can also be exposed by removing the two screws holding the crew cab compartment to the frame. But in order to get to the rear gear tower you must remove the weight.
Of course, once you unscrew the weight from the frame you will encounter another issue, but I’ll let you figure that one out yourself.