I agree with Fat47, here is a picture of my 49 Super gauge. I mounted a volt meter behind the stock face where the Amp gauge should be. Zero is 12 volts, anything to the right is more so I know it's charging.
Gauges are on hold as future me problem. Took her for a drive around block last weekend. Couple bugs to work out. But running.
Cool ride,seldom seen. Congrats and enjoy. I had a 52 hardtop for a bit as a 16 yr old, at the time it just wasn’t cool enough, away it went.
Looks great. Mine was too much for me to take on at the time with little tools and skill. But I did do a **** ton of research for parts over the year(s) I had mine. Be careful with the back gl*** as it's '50-'51 Buick/Olds 98 only.