Looking at our original radiator, support, fan blade etc., we're convinced that there was no factory fan shroud on the car which is an early production GT, 4spd Coupe. Any corroborating info. is appreciated.
Likey if your Marti reports says "heavy duty cooling". The GT 350's got it. But the A code, might not have been a necessity. You also might want to look at the Osbourne Assembly manual. And, I'm sure somebody else here is going to reply.
You aren't referring to a 1967 Shelby? If that's the case, then perhaps your question is best asked on http://www.concoursmustang.com