Setting the sppedometer to zero

[norcalslim]

I replaced instrument cluster because of a fire under the dashboard. I also replaced the speedometer cable but when I did, the needle sits at 15 mph even while the vehicle is stopped.
I also replaced the plastic gear in the transmission but was told I had to use a 19 tooth gear because the 18 tooth gear (original) was no longer available. The dealer told me that the extra tooth would cause me to be 5 mph off.
Now, with the two problems combined, I am off by over 20 mph.
How do I set the speedometer to zero and calibrate it to read my actual speed, or at least closer than it is now

 

[matey]

I would go to a wreaking yard and get the right gear for starters and to turn back the clock is tricky and illegal. There are two ways one is to hook up an electical drill and spin it all weekend the other is to get a couple of hair pins and carefully release the cam behind the numbers and spin till ya get to the number you like. This information is given as just that. information. I do not encourage breaking the law

 

[VOATMJ1]

I think you missed of what he was talking about. He wants to set the speedometerto zero, not the odometer.

 

[matey]

ya i know i got the message allready

 

[gavin]

there is no "easy" way to fix the speedo problem, since the speedometer only goes as low as 10MPH.
You could either remove the needle stop, pull off the needle, and make an educated guess where 0 would be when you put the needle back on.
Or, not quite too recommended unless in an empty parking lot or something, remove the cluster cover, follow somebody doin 20 (or whatever) and put the needle on at that spot.
Make sense?