been down this route myself-- they can be repaired (depending on what exactly has broken within the odometer) but to be honest you may as well save yourself a lot of grief by replacing the whole dash- cheap enough on ebay mate- g'day
I'd check out the following thread from the Corrado forum regarding bust odometers and their causes, as it is probably something similar. As 16v said though, the easiest thing to do is probably to get yourself a new set of clocks from a scrapyard/ebay.
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