Just be careful with your seletion of push buttons.
You're only activating a relay with the solenoid wire,
so it's not 60+ amps going through the pushbutton, but
starter buttons are still rated at a higher current
then the standard 3amp eletrical switches you see in
I'm not sure what current the solenoid draws, but try
to use a switch specifically made for the push-button
starting (all of the ones I have seen were insulated).
Probably to keep you from becoming a circuit between
the white wire and the return on the car.
JC Whitney has an illuminated switch for $70 U.S. that
comes in yellow, green, red, blue or clear.