A100 3 speed manual trans speedo ?

A friend has a 68-70 ? A100 panel van V8. (unsure of year/ but it does have the wing crash pad).
It has a 3 speed manual trans. The speedo cable goes into the passenger side of the trans. Unsure of the trans model/ID
I crawled under to look at the speedo connection (at the trans). I could not see the aluminium adapter for the speedo pinion adjustment part. Like it does not have the aluminium adapter.
He changed rear end ratios a while back. And now his speedo is off. If he's going actual 42MPH/ the gauge shows 38MPH. So the speedo gear needs to be spinning faster/less teeth.
Does anyone know what 3speed manual he may have? and does anyone know if you can install different speedo pinions / need information Please Thank you .

nobody knows anything about A100 3 speed manual transmissions speedo gears ? Can the bell housing on the small block 318 accept other transmissions, Like a borg warner T85 os someting else ?
Maybe someone install a different manual trans before he bought it.

I'd just drive it to local transmission shops that do old vehicles and they can tell him what transmission it is and take out the gear that he wants to change and see what tooth number is on it, see if they have the size that he needs or if they can order it. They may also be found on eBay, but usually high priced around $40. Shop around locally.