A body K member

If you have a choice, look for a 1973-76 K member. They have a better motor mount design and the better steering linkage.
A unit from 1968-72 is a good unit too.
SKIP the 1967 model. It will work but the idler arm mount is inferior to the 1968 and later models.
A 1973-76 model isn't hard to find.
Good luck.