Ok, pitman arm and I thought Ive read the length of the column is different.
The length of the steering column, or more correctly the main shaft is different. There is an adapter you can by to mate up the two.
The size of the input shaft on the two boxes is also slightly different. As such you will need a different coupler between the box and the steering shaft. T he above adapter will take car of that too.
The pitman arm may be different depending on what power box you have. Manual boxes for all years have the same size pitman arm...the smaller size that early power boxes have.
Personally I like power over the manual, then again mine is a street cruiser!
Jason