To avoid breaking melt-rivets: NEVER clean a Model M without having it secured in the LOWER chassis. You will have full access to what you need to get at and a much lower risk of damaging rivets.
When the backplate assembly is removed from the ABS housing, store it upside down, rivets up, on a flat surface. "Oh noes, this wear-"no. Just no. It does no lasting damage to the springs when you do this properly, and prevents additional rivet breakage. Oh, and only ever do this with the keycaps ON. If you do it with the keycaps off, you will damage the springs and barrels both.
Do not
ever pull on the cable from the controller/backplate side for fixed cable keyboards. Not ever. The ground strap can be damaged very easily, which means the cable is scrap. If you do this to an M5 or M13, the keyboard itself is essentially scrap - the Y-cables are unique per model and purest unobtanium.
If it doesn't actually need a bolt mod, don't bolt mod it. Bolt modding is a risky proposition and you can scrap the keyboard. Find something to practice with before you do it.
Don't. Mess. With. The. Controller. Handle it with extreme care, do not let it near anything but isopropyl alcohol and air, and be gentle with it. There's a chance it will be much more brittle than it looks, even though they are tough, and fixing them can be a huge pain. If it has a heat shield (metallized cardboard) do NOT lose it, do NOT damage it, ALWAYS reinstall it. These were used on a variety of controller variants as they put out sufficient heat to damage the ABS chassis.
When all else fails, you can often find replacement parts from Unicomp. Though obviously you want to avoid replacing parts if you don't have to.
Think that's about everything!
