I need some ideas on how to install this fan set up

Did you figure it out?

How about posting a top profile of the fan shroud laying on the radiator?
Also, a 45 degree angle or two.

A pic as if you were looking down from the top of the rad, so I can see what the side tabs on the fan shroud look like in comparison to the rad.

Based on what pics you have posted already here is an idea:

Since the tabs on the fan shroud do not have any meat to grab really on the rad, remove the side tabs on the shroud and fabricate some nice looking 16 gauge sheet metal tabs shown in red so that they pull the shroud snug to the rad when you tighten the rad to the car. I recommend 4 tabs to match up with the 4 rad bolts. I also recommend running a little weather stripping btw rad and shroud so they seal and dont rub.

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