I'm thinking of going back to the idea of modifying my battery box, attaching a new charging connector, and replacing the key with a breaker switch because I hate carrying the key, have to have a good lock anyway, and I could save a few ounces weight. Reading this as tutorial:
https://www.electricbike.com/the-onoff-switch/
Maybe this switch:
https://www.monsterscooterparts.com/...yABEgKJs_D_BwE