I just Bought a 65 Fury 3 and I am dealing with the same thing and trying to figure out How and If it can be done so if there is a way Id love to hear it.
The person I bought the car from took a Small block 318 and dropped a big block 383 in with out changing the trans so nothing lines up I found a trans but it is a Linkage trans and not a cable so I need to figure something out
get a hurst rachet shifter or other aftermarket there is an adapter bracket that bolts to the pan and works great
I have been using it for 25 years for street and racing works good and easy to adjust