UPDATE: I pulled the fenders & doors this morning, and found IMHO proof that indeed my drivers side UPPER ONLY, is supposed to be the stamped steel, while the lower is cast. Other owners seem to provide evidence that other original cars built in SJ AFTER mine, have hinges that are both the cast type. (uppers and lowers)
The "smoking gun" for my car having the upper as original, that is, not a replacement hinge, is the dumb-dumb sealant still stuck to the top of the hinge. I can scratch through the paint on the dumb-dumb sealant to check it further, but unless this sealant was maticulously done while the car was like new, say at a dealership to stop up a cowl leak (Barstow California Desert area...not likely) AND while they were in there changed BOTH of the upper hinges AND repainted them to match perfectly AND the other set of doors with the same type of hinges I have (steel upper, cast lower) dated Mid December had BOTH upper hinges replaced too AND was maticulously repainted...Yeah, a little far fetched!
It looks to me that the assembly line workers must have begun using the stamped type for a while and possibly went back to the cast type for a stretch of time. As for my car, I am going back to how it was built, possibly against what judges might wish to see on my hinges, given it's build date. I already have another set to replace the "known to be replaced incorrectly", right side upper.