12v key start solenoid will not work on a foot activated 6v starter. The nose cone is cast for the accommodation of the solenoid activated bendix. One cannot swap nosecones because the 6v and 12v armature shafts are different diameter.
Soooo.... you will need a 168 tooth 12v flywheel/ring gear to go with a 12v key start.

~~ Jethro
1954 3100
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