The speedometers for all MKIIIs (all Toyotas with mechanical speedometers, I think) run at the same input:speed ratio.... In other words they may all be interchanged and they'll report the same speed. The speed at which the cable rotates is another story; It's a calculation of tire circumference, end gear ratio, transmission worm gear and the driven gear which then connects to the speedometer cable. If you change any of these you upset the accuracy of both odometer and speedometer.
While you can recalibrate the speedometer, you can not recalibrate the odometer. Ideally, you would change the driven gear so that it matches the rest of your setup as closely as possible but that's not always an option.... the W58 uses a different size driven gear than the R154 and A134E, so you can't just swap them. I never managed to find one but if you swap in a W58 and have a GTE LSD you might have luck finding a compatible driven gear from another Toyota which was equipped with the same ratio end gear and a W series transmission.
__________________
If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum.
If you're so inclined I'm always more than happy to accept tips via PayPal. 
Tip Jar ---> 
|