[Yosemite Sam]

There were 3 tillers available for our Cubs a #1, #1a and #2.

Quite frankly I don't know the actual difference between a #1 and a #1a. I'm guessing the difference was the mule drive (bolt on or quick attach) someone will be along shortly to confirm or debunk this.

The #1 and #1a tillers had a 26" cutting width, with 6" extensions available that could be added to one or both sides giving you a 32" or 38" cut. The #2 tiller had a 38" cutting width.

In any event, any of the 3 will work fine with your 122. Even if your tiller comes with the Q/A mule drive, it will bolt to the existing holes in the front of your tractor frame.

The only things that I see missing from your list, is a 3 point hitch and the correct lift pin are also required to raise and lower the tiller.

I also suggest a spring assist or hydraulic lift, to help raise and lower the tiller, because they are HEAVY!

If you have a use for a tiller, you will never regret getting one, they do a fantastic job and really are great fun to use.