[Hutch]

2low72
Some of them have ball bearing slides and some of them have nylon runners.
I am unsure of which models have what kind though.
I like the ball bearing ones over the others myself.
I could be wrong in this line of thought but:
I think they should both interchange but you would have to change out the tray and the carrier with it.
The only other difference that I can think of is the 67 had a different faceplate, which was a smoother finish