You can wait an hour if you like. Personally I wouldn't bother, until someone can explain the myth of 'residual current'
Screws on the back are dotted torx. If I recall they are size 6. A small ratchet is useful. Disconnect. Release nut. Leave screwed on. Tug ineffectually at wheel
You may need a puller but the Edd China way of bracing your knees behind the wheel is often effective. Make sure you're straight ahead and / or mark the position of the wheel on the bolt.
Nothing should go sproing.
Having said that, I'm not entirely sure you need to take the wheel off to change the ignition switch. Can't you just remove the shroud? You may still need to remove the outside of the wheel, but you can do that with allen bolts that attach it to the hub.
C