Hi guys, it's been a few years since my last confession... My kids like to play in my 77 deluxe micro. Despite warnings my son occasionally turns the wipers on (why do these work without the key?) and after the most recent time the wipers don't work. I've managed to remove the wiper motor and arm unit. The steel drive axle that comes from the gearbox - which rotates constantly in the one direction when the wipers are on - moves freely out of the gearbox which I'm guessing isn't quite right, ie you can pull it all the way out. The steel shaft has a cross-hatched area at the inside end, it appears to engage something inside the gearbox - it was dark and I was wearing my crappest glasses but the corresponding item inside the gearbox appears whitish so I'm guessing nylon parts in there. Are these components replaceable? The unit seems to be otherwise ok, ie. when the arm selector is moved you can hear the unit power up and step up through the speeds. I'm guessing the motor is ok but maybe a nylon component is stripped so: no go at the wiper blades. I haven't taken the unit apart yet. I have a spare unit but it must be an earlier model (70, 72, or 73, I forget which but it's one of those) as it has a larger motor can and it looks like it would mount the other way up, if that makes sense, so I can't just slap that one in. Can the gearbox be pulled apart and repaired? Can I steal anything out of the other spare unit to make it work?