35olds

My '70 442 W30 had been given a cosmetic restoration before I bought it and I'm now going over everything. The body is currently off and I'm preparing the underbody and firewall/cowl for a repaint. I've seen photos of other restorations where the cowls have been painted a somewhat more flat black rather than a semi gloss. When I pulled the A/C box off today it revealed the original paint behind it and a marking (see photo) where the paint behind the A/C box was a more semi gloss (the rest of the firewall has been painted over when it was detailed in a more flat black.
My question is what have others on the forum have found ?? I want it to be an authentic restoration so I'm trying to determine if this semi gloss is correct or is that area of paint age effected somehow.
Appreciate any thoughts.

35olds

Thanks for the PM's received from some very knowledgable people on this request. The feedback received all matched and I'll be running with a gloss level as close as I can to what was behind the A/C box.