Looks like you are on the right track. I'd agree that the ITB hole is in the wrong place. Front and center, down low on the bumper would be better place to arrange a RAM air duct. I really like your wind tunnel! I race my car a couple times every year and am amazed at how much the other guys are leaving on the table in the aero department. I got the quickest ATX ZX2 right now and would like to think all the aero mods I've done is one reason why. You can learn a great deal here about aero.
You should consider the front air dam along with your belly pan. I'd also try to get those front tires shrouded and get moon eye disks on the front wheels and make some rear wheel skirts.
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