Jo, I don't think that the foamy bits are really all that necessary. Like you said, they may help channel air to the radiator and maybe keep junk out of the areas beneath the headlights. The foam may help to stop the front bumper cladding from rattling around in the wind.
The little metal bit in the middle, to me, does offer structural integrity to the cladding as that is where the front cladding is attached to the VX, behind the license plate. It seems that without that metal bit the cladding might flop around in the wind when going down the street.
That's my two cents.
Can't wait to see what the whore becomes when you're done with her.
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