Nel621, I was planning on looking for a recent post regarding the early cluster/speedo --posted by you?--so I could report my own findings having just taken apart the speedo to repair the odometer on a 1980 245.
I can't tell you if I did things correctly but both the odo and tripmeter are working again. I did have one of these apart long ago but the fix was different and it left me with no tripmeter. At that time I ripped out the drive to the tripmeter as it always stopped on the same digit. At the time I had no idea what was actually wrong--it made me dizzy to try to follow the path of motion--never did pinpoint an AHA! Guess it was sheer luck but the odometer started working again.
This time the tripmeter always stopped between .8 and .9 and I intended to do as I had done before. On taking it apart it seemed the drive to the auxiliary service counter seemed very stiff. I eliminated it and spun the first drive gear to advance the miles---it has lost over 5,000 miles in the past year or so. The digits advanced to what I thought an appropriate 268+. At that point I buttoned it up and it is all working.
Caveats---I couldn't see anyway to remove the speedo needle but to just pry it upward. I have no idea how they get attached. The needle came loose leaving the spindle post. The spindle is spring loaded and will settle in a position that would have the needle pointing straight down. I had pulled the 0 stop pin to see where the needle would rotate. The pin stop is sort of a rivet--no chance of these fat fingers dealing with such a tiny piece--that and the speedo needle----a touch of super glue for each seemed to suffice. I gave the glue overnight to cure. Good Luck---Dave