1952-59 Ford Trying to find the correct driven gear for my AOD transmission

I am trying to find the correct driven gear for my AOD transmission, the necessary info is below.
The tire size: 215/70-15
Ring and Pinion Ratio: 3.89:1
The only thing that I do not know is the exact tooth count on the inside gear but I know that it is either 7 or 8

The transmission that I have is this one: https://transmissioncenter.net/shop...-3-dominator-junior-dominator-junior-extreme/

Which one should I but what gear count ? or where should I start ?

 

You already asked in a separate post and we responded with sites there. They are inexpensive enough and easy enough to replace, buy one of each...

https://www.jalopyjournal.com/forum...-tooth-count-for-my-aod-transmission.1313476/

 

with my rear end ratio/ tire size, i couldnt get any closer than about 5 mph off with the gear changes. So i gave in and bought a the smallest GPS i could find.

 

Where did you get that - make, model, etc ?

 

Bought GPS on the Bay... https://www.ebay.com/itm/195913384787

 

There is a company in Texas (Texas Industrial Electric) that makes conversion “transmissions” adapter. They are easy to calculate if you your city uses those speed mph checkers you can drive by. I use one with a 90* off a T-Bird. I’ve used one for 5 years with the speedometer correct at any speed.