bell wire fork terminals

I have one of the new 2nd Gen Ring Doorbells and with it having the option to use existing bell wire, I was wondering what size Fork Terminals I need to purchase to fit behind the screws?

3.2, 3.2, 4.3 or 5.3 mm ?

Also, not sure about the whole diode/resisters thing. If I have enough voltage at my current bell wires, do I just connect those?

I tried to watch some you tube videos. One bell, the light remained white on the bell while it was connected to the bell wire, while charging. Is this the case or will that stop lighting up after it is fully charged?

Thanks for any answers.