273 Build
My '65 original has the DCPD emblem stamped on it. I dont remember seeing AC on mine, but it is the thick 3-core. By the looks of yours, it seems similar or the same. When I'm back at the house my curiosity is peaked, will have to check the other stamps on it.
Only had problems with it once, out on the freeway, 115 degree heat between vegas and mesquite. It blew a crack thru one of the rails that had been slightly damaged by a rock. Long hot day at a gas station in mesquite while I waited for my brother to come out and put it on a dolly to bring it home. A Torch and some solder and it was good as new.