Herman,
Mine is a 66 C code C4, but I don't think it matters. My understanding is that all fans were fitted with a shroud. the original was a pressed steel part, which didn't fit that well but there are now plastic and fibreglass ones availiable. I saw one the other day at Mustang World in bundoora Melbourne. Bear in mind you have to make sure that your fan protrudes from the shroud by 2/3rds (someone please confirm this, it may be 1/3rd)
you may need to take some measurement depending on whether you have a two or three core radiator.
Hope this helps.
BTW do you have an overheating problem? because the shroud is supposed to be a critical component of the cooling system.