Goldsmith May 2017

[Steamcar]

I can not tell you the answer. I know the 3 machines are not identical. They may have been made like that or it might relate to the amount of work done or how extensive the restoration was. The spoke pattern on the wheels you mention is different as well.
Perhaps the thicker wheels were needed to cope with the single central T ring.

Here are a few more pics that make an interesting comparison.