Very little of the fitting is filing, and if it is needed, only a few strokes. If the barrel stub (forcing cone) does not have enough BC gap, it is filed.
The ratchet hub and ratchet teeth seldom need filing.
Much of the wear is on the end of the cylinder arbor and inside the cylinder where it fits. That is the reason for installing yoke shims and/or "stretching" the yoke to fit.
Actually, if your extra K-22 cylinder and the M48 are close to the same period of manufacture (within a few years), it may not even need any fitting.