I have a t18 trans from a '75 Scout II (was on a 345 v8, w/ Dana 20 t-case), and a guy is asking me if it will fit a '70 800 with a 196 4-cyl. My experience with this specific topic is limited, so: will it fit?
The input shaft for a four cylinder t18 is somewhat shorter than the same item used in a sv application. That is why we call the four cylinder bellhousings...the "pancake" version since they likewise are very shallow.
So no...the sv t18 won't work behind a 152/196 engine unless it's input shaft is swapped out.