Nice find! I have two 1976 Fisher Pierces that came with my 1976 McGraw Edison Nighthawks.
These are fantastic PC's. The FP's are long lasting ans well sought after PC's for collecting. The tall hats were my favorites from the early-mid sixties.
I started collecting when I was 14 and my dad who worked for an electric co-op brought home some brand new in the box LM Spherolite Juniors that were being replaced by MV. Next was in 1964 when the General Electric Supply salesman brought dad a salesman sample GE 175W Mercury with the heavy "Bohnlite" head which had the red epoxy encapsulated ballast in it and the fully enclosed GE globe assembly. We installed it on a 20 ft pole and that was when the fascination started.
I have been trying to located some of the early GE "pop top" twist locks from the early-mid sixties that had the horizontal glass PC tube or the LM Tabet Mfg. PC's from the same time.