Electric fan shroud to radiator fasteners

Hey all

I've got a 22"x4 row champion radiator with a dual electric fan shroud for the radiator.
Does anyone here know what U-clip or kepnut would work to secure the shroud to the radiator?
Bolt size, and reach info for the U-clip would work great because I haven't any idea what to use.
Additionally, whenever I ask the people that sell the shroud and radiator, they haven't a clue either. It's like they have never done it before. One would really think they ought to know....

Electric fan shroud to radiator fasteners
Author: greatscot3