there's a broken plastic tab on the 100's wheel so it doesn't trip the next one - easiest to find another set of number wheels and change the whole thing [carefully] - I haven't seen them reproduced, but a speedo repair service might have something, and if you're determined, you might be able to swap the 100's wheel with the far left one [100k] where the tab isn't needed
also
see this , and the complete speedo unit is the same 55-59
Bill
