Seems to me that if the bellhousing you are using was set up to hold the foot starter mechanism, all you would have to do is put the foot starter back on, and use a 6v starter with switch as per original. Might need to change the flywheel or pinion gear of the starter to match. The 6 volt starter will work fine.
Alternatively, You could use the foot starter mechanism to hit or work a switch which will activated the starter solenoid. This should be pretty easy to do.
Kurt
