Some nice relays to consider
https://www.amazon.com/Pack-OLS-Relay-Switch-Harness/dp/B01NBAO1SA/?tag=ihco-20
https://www.amazon.com/OLS-Waterproof-Relay-Switch-Harness/dp/B01N66W2XF/?tag=ihco-20
and connectors for cutting into ignition wires for a push button switch
https://www.amazon.com/Solderless-Quick-Splice-Connector-through/dp/B01N3PYV89/?tag=ihco-20
https://www.amazon.com/Pack-OLS-Relay-Switch-Harness/dp/B01NBAO1SA/?tag=ihco-20
https://www.amazon.com/OLS-Waterproof-Relay-Switch-Harness/dp/B01N66W2XF/?tag=ihco-20
and connectors for cutting into ignition wires for a push button switch
https://www.amazon.com/Solderless-Quick-Splice-Connector-through/dp/B01N3PYV89/?tag=ihco-20