Toyota Repair: Speedometer malfunction in a 1992 mr2, nylon gear, salvage yard

Question
In the transmission what does the plastic gear from the speedometer hook up to? If you have a picture, please email it to me. Can it be replaced by pulling the axle or does the transmission have to come out?  
The problem is that the speedometer does not  work. I can attach a drill to it at the transmission and it works. I can spin the gear and it works. It appears in the transmission there's not another gear it is meshing up to. Thanks, Don  

Answer
Strange conincidence, we recently had a 1991 MR2 with the same problem, it turned out that the nylon gear in the transmission that is attached to the differential ring gear had disintegrated and so the speedo gear did not turn.
Remove the speedo gear housing and you should be able to see the other gear inside the transmission using a flashlight and a mirror, if it's not there things can get a little complicated.
The transmission has to be removed and disassembled to get the ring gear out, then the side bearing is pressed off so the new drive gear can be installed, most of the cost of the repair is labor.
Be prepared to spend about $1,000-1,400 depending on who does the work.
Another option may be to just find a used transmission from a salvage yard that specializes in toyota used parts.