Just an update on the search. Bought some more wall art off Ebay.
The gear set sure is nice looking NOS but just as I expected not all SM420 yokes are created equal. The drive gear is about an 1/8" smaller than mine. But the driven gear is the right length.
https://goo.gl/photos/dhAsKarrVdY23Srn8
https://goo.gl/photos/JgAYpcuoybXV9fys8

Back on the hunt. If I could just find a 14 tooth driven gear I could use the drive gear I have.
Ken


1951/54
Basketcase