Many Shay locomotives were built to relocate the wheels on the axle. The drive gear is a two part half C shape which is bolted to the side of the wheels. Therefore it can be un-bolted, wheels pressed to inner gage, and then half C shaped spacer are added under the replacement of the gear. The wheels fit the smaller gage but the drive line of the drive shaft is exactly the same. W. M. Ritter Lumber Co. changed a lot of their Shay locomotives as they moved them around to various located lumber mills.
With the universal on the drive shaft, it is totally unnecessary for the drive motor axle to be in alignment, vertically, OR horizontally, with the center line of the drive shaft in the trucks. As proof to this statement, take a look at the last (most modern) Shay built, now Cass #6 and you will see that the drive motor shaft is over 6 inches above the drive axle in the trucks. Lima had no problem with that design. And it does not matter, because of universals joints, if the drive on the motor is several inches away from center line of locomotive than the drive axle on the trucks. Just the same adjustment happens as going around a curve, where it all flexes as needed. Take note, RC&BT which dismounted the drive motor cylinders and cast a new spacer against the boiler to make the drive line in exact center line with the trucks axil drive. That was all wasted money on the casting and remounting of the cylinders. Again, former WMRR and Cass Scenic RR #6 has no problem with drive shaft having different alignment of drive motor axle and wheel truck drive axle height.