E Brake drum on a diesel trans

[alberta mac]

my 78 fj45 has a b and 5speed trans in it, Diesel. I also have a 4 speed trans with the brake drum set up on it.
I need the brake drum set up to go on my 5 speed.
Any thoughts or are the splines different ?

 

[jim land]

What year is the 4 speed ?
If it is mate to a split case it could work with your 5 speed