The markings are clearly 1, 2 and 3 with the fourth a NEGATIVE sign

To me they look like "1" (not a "-"), "2", "3", and a really weird "4".

Is not the negative sign *right next* to the pin linked to the case

But with your help along with the one pin (yes, it's the (-) one) in common
with the case pretty much confirms polarity.

Thanks!

Nighty-night! Lights out!