When I got my 1973 Cutty Supreme it did not have a fan shroud. Instead it had a plastic shield ontop of the radiator mount that hung out over the fan blades. I know the car was 100% bone stock. No alterations, no nothing. I just thought the fan shroud was missing. I confirmed through old pics of my first '73 CS that it did in fact have a fan shroud. So I purchased a fan shroud and attempted to install it. Well, either the shroud was going to go on or the fan was going on, but not both! I removed the fan (non-clutch type) and aluminum spacer between the fan and water pump pulley and the plastic shield. Installed the shroud and hand tightened the shroud bolts and then tried to put the fan and spacer back in. Absolutely impossible to achieve! No room to do it. So I went back to my old pics of my first '73. Tried to find a pic of that aluminum spacer between the fan and pulley because I seemed to recall that it was ALOT shorter than the one I was currently working with. It was then that I noticed that my old '73 had the emissions sticker on the fan shroud where you normally find them. White in color with black lettering and right ontop of the shroud where you would normally find them. The '73 I have now has the emission sticker on the passenger side fenderwell. Yellow in color with black lettering. My old '73 HAD A/C and NO rear defrost. My current '73 has NO air and HAS rear defrost. Then it dawned on me. Is it possible that my current '73 was built and destined for a northern climate? Having no shroud and just a shield on top for the fan blades? Does this make sense?

 

I don't think that "destined for a northern climate" has anything to do with it. I don't know the answer, but I do know there were '60s Cutlasses that didn't get shrouds if there was no AC.
A Product Information Manual (assembly manual) should have the answer.

 

there is your answer.

non a/c water pump (short),standard fan blade with non heavy duty cooling

youd probably have to get an a/c water pump which is longer,to make the clutch fan or flex fan fit inside the fan shroud.

 

Of course, longer pump means different pulleys as well. A fan spacer with the current pump might be the easier choice.

 

youre trying to fix something that isnt broke

long story short,leave the car alone

 

Is the car having problems with overheating? If so then maybe it needs a better rad otherwise just go with it as it is.