What PARTS did Hurst and Chrysler put in the Super Stock Barracuda & Dart not in other factory cars

Other than a stock A-Body BB radiator, aluminum seven blade fan and clutch drive, eight blade water pump and no shroud, and probably no thermostat, was there anything else to make the cooling system special other than no shroud mounted?
And as for the clutch drive, it was torque driven, not thermostatic run... was this special to this fan unit and engine?
Just curious to get this right...

I have no clue. Everything I have read said the cars came with a "heavy duty cooling system" whatever the hell that consists of. Seems you have a better handle on it than I do.