If you want to retain the look of the stomp starter, use a floor switch like the one a Ford or Allis-Chalmers tractor uses. Run a #12 or larger wire from a full battery voltage source like the back of the ammeter to the switch, and the other wire from the switch to the "S" terminal on the starter solenoid. A dash-mounted switch is wired the same way. Be sure to use a very heavy duty push button capable of a 40 amp initial current surge or so.

The old external-regulated alternator requires the use of a 4-terminal dedicated regulator that's a pain in the butt to wire, and it's very failure prone. Switch to a 10SI internal regulated alternator if possible. The original DC regulator cannot be modified to control an alternator.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!