Yaktx: Where's the EGC connected, since it doesn't look like it's headed for the ground?
I assume you are referring to the GEC, meandering off to the right in an upward direction? The answer is nowhere. The house was replumbed and the plumber never replaced the ground clamp. The deadfront was there.
Nearly all Stab-Lok panels had one row of upside down breakers, which was legal at the time.
The lack of a main breaker does not mean this is a subpanel. I assure you the meter was right above this panel. In this case, it is service equipment which is in violation of 408.36(A). This service appears to be from the '70s, and my vintage NEC collection tells me it was illegal then, too. Nevertheless, many such installations were approved in my area during this time.