Doing a bit more digging on this Wide front thing.... Here is a bit I scanned from the Cub Jr Brochure it clearly tells the reason for the single front wheel in the first place was to keep the frame from twisting.

There had to have been a reason Massey Ferguson kept this Cub Jr wide front from 1919 until it donated it to the Smithsonian Museum in 1960 and I believe it was because this was the first Wallis tractor to have a wide front mounted on.

The funny thing is this tractor sat arond so long they didn't even know that it was a Cub Jr and donated it as being a Model K

I have several pictures of this tractor in the Smithsonian but all are from the side or a 3/4 view hiding detalis. If you look at this picture it appears that the front cast support for the front axel is bolted into the frame and Not rivited as the bolts stick way out in this picture. I wish I could get a look at this tractor in person to see if I could read out any other clues but for now I hope this will possibly bring people out of the woodwork on this subject that may have more info.

Joe