I understand SEGA style series for what it is, and have a good friend that races a fast Pontiac in the SEGA group.
By 1974 Pro Stock cars were panel built, tube chassis, Lenco cars, and had a lot of go.
For me there is no way I would skimp on a roll cage, or the funny car cage around my head to be period correct. Not allowing a roll modern cage is senseless to me.
I am also very happy with my safe plastic fuel cell, and my NHRA required SFI approved wheels. I have a lot of Cragar Super Tricks, but I would never use them on a really fast car.
Regardless of what you run in that group the safety of the driver, drivers, and the crowd has to be the first priority. Period correct does not address this in today's World.
One suggestion I would make to your series is the mandatory requirement of 35-spline axles, real spools, and period correct or not 5/8" studs in the axles.
No track operator wants a group in that blows a rearend out, oils down the track, or shears a wheel off to slow their program down.
I admire your efforts in trying to start a new group.
Tom