just did it this weekend, on my 87 420SEL.
I just pulled the pieces off, they snap onto the stems when you got to put them back on.
My seat switch, driver side, went bad (rattling items inside)...replaced it with similar but not exactly same switch from junkyard....fit was 95% so I had to fiddle with mounting screws somewhat to get it to the point where the adjustment pieces would snap onto the new switch's stem but it works....so far, no blown fuse...
Network Integration Engineer
MCSE, CLP, CCNA