After nearly 35 years, my car is finally in the shop for a full restoration. I'd done a partial back in the 80s and then it was parked and became a garage table until this year. After blasting there was a distinct sheet metal marking revealed, right on the middle of the tail pan, left side. I'm guessing that "Weirkote" rolled steel came from a long-gone Weirton Steel plant in WV or southern Ohio, and the part was stamped in the Cincinnati area around Norwood, possibly Hamilton/Fairfield as were some of my other parts, then shipped off to Van Nuys.