LOC 622 is a page designation in the Lionel postwar service manual. LOC is short for “locomotive”. This particular page is reproduced in the “Greenberg Repair and Operating Manual for Lionel Trains”.
I have not done this process. When the worm wheel needs to be changed I remove the magnet. The glue that retains it is usually brittle and with a thin blade I have been able to pop the magnet off. It is important to mark the magnetic so it is reglued back in exactly the same orientation. The old glue and any oil or grease have to be cleaned off. I use JB Weld to reglue the magnetic. It has to be reglued so it will be very close to the wheel, but not touching it. If the thrust face of the bearing is worn, which common on the worm wheel axle, a shim can be added to keep the wheel from touching the magnetic. Thrust washer 671M-23 will probably work. Or the bearings can be replaced. If the wheel rubs on the magnetic this acts like a brake and can noticeably reduce the performance of the locomotive.
Lionel normally provides the gear side wheel with the axle installed. When wheels are removed the usual practice is to remove the non gear side wheel and leave the gear side wheel and axle as a assembly. This allows the gear teeth to be in mesh before the the pressing operating starts. The 622/623 locos were a special case. For some of these locomotives Lionel provided the gear side wheel, axle, and axle bearing as an assembly. The axle bearing was pressed in the truck frame with the wheel and axle already installed. This requires that the worm wheel also be pressed on the axle at the same time. The reason for doing this was to avoid pressing the upset serrations on the axle, the ones that retain the worm wheel, through the bearing, which scores the bearing. Pressing the serrations through the bearing is common practice on other locos.