The Bolens axle was cut down and drilled. The shorter end didn't need altering. The length was just right and the original wheel retaining bolt hole was also used for the model. The other end was a pain in the ++++ though. Tough to hack saw through, although it could have been worse, but the 5/16" hole was a ( censored word ) to drill. Finally got through with an assortment of drill bits, cutting compound and my lashed up drill press using various speeds and lots of naughty words. Luckily I only had to drill this one side.
Now, what to use for the front axle bushes. A long time was spent looking through my piles of bits and weighing up all the options. Some bits had the correct OD but too large on the ID and so on. Still wanting to use what I had to hand, a piece of engineering plastic was used. Not sure, but I think this is Delrin or Acetal or similar. A short piece was tapped into copper tube to hold it rigid while drilling in my Unimat lathe. I was surprised to see blue swarf as the material is black. After drilling up to 1/4", the bore was opened up on the drill press. Can't remember the drill size but slightly under the OD of glacier bushes which were tapped in afterwards. These had an ID of 3/8" which was the bolt size I used for the king pins.
If these bushes were later found to be unsuitable they could easily be changed. So far, with a few test drives that the Showman and I have had over rough ground, no problems have been found.