All good info- If this is attempted the lever between the solenoid and starter drive would be needed and also the metal "cylinder" that fits into the 12v solenoid would be needed-it pulls the lever when the solenoid is activated
No- - - -just obtain a 6V solenoid type starter, and either install a solenoid with a 12V coil, or use a low resistance, high current resistor to control the current flow in the solenoid pull-in winding. The resistor is a simpler, MUCH less expensive option. The solid steel plunger on the 6V starter should also work on the 12V solenoid if you choose to go that route. It IS NOT possible to convert a foot pedal operated starter to solenoid operation.
Jerry