Feasible to convert power windows to manual crank on 240 ?

There have been very few times in the life of any of my 240GLs when all
four of the power windows were working perfectly, hence requiring the
old pop-the-switch-and scrape-the-contacts routine, a chore that
invariably gets left undone for long periods of time, usually when it's
gotten to the point that all but one of the windows is dormant and it's
100 degrees in the shade.

It's at those times that I wished that I had manually-cranked windows.

So, I'm wondering how much of a chore it would be to convert them ?

 

Pretty easy really, I've only ever converted the other way around but it'd
be fairly trivial to replace the power window motors with manual crank
window regulators. Never had much problems with the power ones myself
though, perhaps you should try cleaning all the switches at once and apply
some dielectric grease to them to keep them from oxidizing.