Sorry to repeat what was known to you, ha! The grill blocks are great looking. I, too, have been looking at upper grill opening blocks but am more concerned about the lower openings. Looks like you nailed the solution! I'm going to copy what you have.
Now, what else are you hiding . . . 
I keep daydreaming that I can afford to have ALUMI-LINE, CLASSY CHASSIS or someone build me an aluminum aero topper (unless Bondo takes off with his) that is contractor-type as to being truly secure. I don't miss having no interior rearview most of the time, and wouldn't want it on a "secure" topper. I like the original Aerolid for the ability to move the center section up and down per load type.
Maybe an extended front air dam like ol'
crabbelle or on this site, like Big Dave. I like the side skirts as well. Even though I have to take a deep breath, first, about it being a Powerstroke, his experience as shared is the truck diesel inspiration, IMO.
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