1960 vintage look battery. Ever open one of these up?

[76eldo]

I have a repro look Delco battery in my garage.
Old and won't take a charge.
I think there's an Optima AGM battery inside.
Anyone ever try to open one of these up to replace the Optima that lives inside ?

Thanks.

[Mike Josephic CLC #3877]

These "replica" batteries have an AGM type battery
inside but it's not an Optima brand battery.  However,
it's the same AGM technology.  That's what the old
Antique Auto Battery people told me a few years ago.

If you take the caps off and peak inside the case with
a flashlight you'll see the small case inside.

Mike