No need to make it more complicated than it is.

Go to your bulkhead connectors.

It is either your top or bottom plug.

Look for the violet wire (that is adjacent to the white wire) this leads to your reverse lights.

Get your power to the console switch from the white wire that is next to the Violet wire.

Power coming out of your switch is now Switched power (power only when in reverse)

Wire this switched power to the Violet wire.

You can also follow the violet and white wire to the reverse switch/connector.