[Arran]

I don't think that I have seen presets for FM stations on any early FM set, those pushbuttons are basically switches, and they switch into the AM broadcast front end. I think that I may have seen a high end Grundig that had presets for one or two FM stations, but that was an electromechanical system with a motor drive, the party selling it thought the set was worth money given the dumb fleabay prices, and once I noticed a tweeter being missing I completely lost interest in even making an offer. The high end Saba sets also had motor drive but I think they worked like a shutter dial brand Z set with a lever for forward, and reverse, up and down the dial rather then actual presets.
Yes, the weekend servicemen were a menace, too many would pick up a Popular Science/Mechanics/Mechanix Illustrated magazine and really make a mess. These days it's half baked online stuff. A lot of people don't understand that wiring colour codes actually mean something, it's not because the guys making the set thought it looked pretty.
Regards
Arran