Which B bodies got fan shrouds in 1970

So, I've been researching around a bit to try to figure out why Mopar did or didn't use fan shrouds and what were the deciding factors as to which cars got them and which cars didn't. I'm specifically trying to figure out the 1970 models because that's what I'm working on right now. One member that has done a good amount of research on 1970 B bodies, and is very knowledgeable on them, told me that the fan shrouds were dependant on axle packages, A31-A36 and if the car was an axle package car it would have a fan shroud on it. I believe that would also dictate a 26" radiator, correct? So was it a 26" radiator that dictated a fan shroud and the 22" radiator didn't get one? There is no factory option for a fan shroud so they must be mandated as part of a package. I have also been told that by 1970 Mopar used fan shrouds on everything and also that all GTX's had one installed. There's some pretty sharp people on this forum so I wanted to throw this out here for discussion in the hopes that I may learn a bit more about subject.

I cant help with the 70s, but your theory sounds plausible. Ive got a 69 dana axle package car, and it has a 26 radiator and shroud.
I think there were other factors that could ad the big radiator and shroud. Towing packages, and a/c come to mind.
Theres always more to learn about our mopars, it seems.

My 70 Charger 500 383 727 8.75 22" rad came with the shroud. 23000 original miler. Just saying.

Research should generally start with the factory service manual. 1970 Plymouth service manual page 7-12 has a full page chart on radiators for B-bodies it lists every engine across the top and Specs down the left side, and it has a shroud column yes/no for each engine. There is every spec you could ask for in this chart.

I do know Every 26” radiator got a shroud. So That is every A/C car, axle package car, and HD cooling car, 440+4, 440+6 with a 4 speed, every 426 hemi, and every Superbird.

When looking at a build sheet there is no box for a shroud. So it would seem that each radiator Part number dictated a shroud or not.

line 3 in center has these boxes
RAD
Inlet hose
ALT
Fan spacer

If this helps: My 70 Charger has 383mag,a/c,26"rad,a/t,3.23 diff.and a shroud.

I’m 99.9% For sure all 70 b bodies with a 383 and bigger had a fan shroud regardless of whether it was a 22” or 26” radiator. And yes all GTX’s would have a shroud.

Thanks for all the responses guys. R413 thank you very much for putting me onto that page, I first looked in the parts book for any notations and nothing came up except part numbers, then I looked in the service manual and looked right past the stuff about the fan shroud.
BLK 68 R/T, according to the service manual, that I've now looked at, in 1970 all big blocks had fan shrouds except 383 2bbl's, 383 2bbl Police package cars were the exception, they had fan shrouds. No small blocks had a fan shroud except Police and Taxi 318's.
I've learned something new from you guys again, thanks.