There was a guy fairly close "SIN Pickups" think his name was Carter. Had him do some custom Alnico 2 stuff many years ago (10 or so).
Was a younger dude but knew his stuff. Not sure if hes still doing it.
Possibly an owner signature but, olllll Plexi, had some work done to it. I know who did the initial work but, found this… anyone recognize this signature?