yes, push buttons are fine, lots of older vehicles used them - but you'd need a different starter, one with a solenoid on it like the key start type

Bill

Moved over to the Passing Lane

"When we tug a single thing in nature we find it attached to the rest of the world" John Muir
"When we tug a single thing on an old truck, we find it falls off" me
Some TF series details & TF heater pics & Rust-a-holics Unanimous parking lot