Voltmeter Expanded Range Question

Hi All,
I want to design an expanded range voltmeter, and trying to decide the voltage range. Let’s assume I have a 48 volt lead acid system.
What is the maximum voltage seen by the voltmeter?
How about hooked to the charger?
What is the lowest voltage you would want to see on the meter?
What’s the lowest voltage you want to pull your batteries down to?
I’m thinking zero on the meter should be 42 volts and full scale 58 volts.
What is your opinion?
Thanks, Qmavam