I got this today via eBay.
The rev counter needle had fallen off.
Is it a case of just pushing it back on or do I need to put it back on and wind some pretension onto it?
I recently had to reset my tach on my tubby as the previous owner had taken the needle off and not put it back in the correct place.
If you can get hold of the kit, the best way I found to set this accurately was to plug an OBD1READ into the diagnostics port and sync the warm idle speed reported by the sensor with that shown on your tach.
see My profile post for a bit more info.
Failing that if your previous tach was working OK and you know what that showed on idle you could just warm up the car and refit the needle to show the same idle speed.
I certainly found there was some pretension when my tach needle was at rest, but how much I can't say.
Paul