[mr48chev]

Nonsense true but harmless nonsense that makes him happy and one of those tractor foot buttons would last from now on with just the amps going though to the S pole on the solenoid.

Cost isn't going to be much more than buying a good heavy duty push button switch and mounting it on or slightly hidden under the dash.

Either way he has to change the ignition switch to one with a key start (total pain in the keester because there are no switches that fit right and the universal ones always come loose.
Install a push button on or under the dash as a start button. Simple, easy and done all the time.
Use the tractor switch and fab a piece to hold his original round foot pedal on it. The hard part of that is finding a short bolt with the right threads to screw that round piece on as I believe it is 5/16 SAE and you only want one a half inch long. That and finding the right diameter piece of pipe to slip over the button on the switch.

The dash I am putting in my 48 (not Chevy but out of a car I owned for years) has a push button on the dash but it is a go to ground push button. I'd have to run a relay with it to have it work if I don't use it for an auxiliary horn button.

Anyhow by now I'd hope that the OP has his setup all put together.