Speedometer Gear Replacement

I have an 89 grandprix with the digital dash. I replaced the whole dash piece and the speedometer/odometer/fuel guage works perfectly. The problem is that i had the tranny replaced and now the speedometer reads wrong. How much of a job is it to replace the speedo gear in the trans and what is the procedure.

I picked up the dash piece from a junk yard for $50 if anyone is wondering on the price

thanks

I think you can get one at dealer. Or call couple trans shops in your area. They more then likely have one laying around.
http://img.photobucket.com/albums/v425/kustomkid54/1998PontiacGrandPrixGTP003.jpg

Sorry, cable runs into trans. One small boly holding a plate. Take it off. Remove cable. Gear sometimes stays in trans. Pull it out, replace. That should do it.
http://img.photobucket.com/albums/v425/kustomkid54/sticker-i-need-a-girl-whose1.jpg