I feel that this piece of computer history needs to be preserved, along with at least my part of the story. Our IBM CE showed me a 'copy' of this. It was actually about a 4th 'generation' copy, but it was formatted and printed to look like an official IBM Customer Field Engineering Notice (which is what they used to tell the CE how to repair equipment). I never saw an original, so as does SNOPES, I suspect that this was just some subtle CE humor.

Abstract: Mouse Balls Available as FRU (Field Replacement Unit)

Mouse balls are now available as FRU (Field Replacement Unit). Therefore, if a mouse fails to operate or should it perform erratically, it may need a ball replacement. Because of the delicate nature of this procedure, replacement of mouse balls should only be attempted by properly trained personnel.

Before proceeding, determine the type of mouse balls by examining the underside of the mouse. Domestic balls will be larger and harder than foreign balls. Ball removal procedures differ depending upon the manufacturer of the mouse. Foreign balls can be replaced using the pop-off method. Domestic balls are replaced by using the twist-off method. Mouse balls are not usually static-sensitive. However, excessive handling can result in sudden discharge.

Upon completion of ball replacement, the mouse may be used immediately.

It is recommended that each replacer have a pair of spare balls for maintaining optimum customer satisfaction. Any customer missing his balls should suspect local personnel of removing these necessary items.