About your other point on the feel of IBM Model F keyboard losing their feel after disassembly. I too have ruined the feel of my first Model F XT keyboard and the key to not losing the feel that I have found is to not let dust get on any of the buckling spring assemblies or the barrels..
You might think that dust is not the reason as these Model F keyboards must get dust in them over the years anyway but the truth of it is they don't as the springs and flippers are protected under the key caps very well the problem of dust arises when the keyboard is disassembled as the springs, paddles and barrels are then exposed to dust.
Best way to avoid losing the feel of Model F keyboards is to put all the springs assemblies in a clean box or better still keep the springs in the exact same order they came out as in put the same spring that came off of each key back and don't mix and match the springs as they have wear that varies between each key hope this info helps
I can't stress this enough no dust and you will keep the lovely feel don't worry.