Yeah, it's obvious from that 2008-09 thread that Mr. Byrd bought some FBS heads from Dvorak, but where you're wrong is that they were for '70s Pro Stock. Why? Because THEY DIDN'T EXIST UNTIL THE LATE '80S.
And the FBS heads were NEVER intended for Pro Stock. By the time Fred had his first few sets ready, Pro Stock was all about splayed valve layouts and aftermarket block bore spacings and patterns. He built them for sportsman and fast bracket guys that wanted to run an AMC or big block Chrysler.
And how do I know anything about FBS heads?
Because for one, I actually owned a set, and I actually talked to Fred Brewer himself many times, both on the phone and in person. I made 3 separate trips to Heartland Park delivering 401 cores to him for customer builds, and watched him race and hung out with him and his son at their pit area between rounds. I made a trip to Elgin, Oklahoma where his shop was and spent a few hours discussing my build and checking out his operation.
You can claim whatever you want, and BS like usual in an attempt to save face all you want.
Edit...Yes of course those are FBS heads, look like mine except mine were CNC ported and assembled. My advice - tell him to invest in a pressure check on them. Many sets leaked.