If it is the length of the radiator, it clips onto the back side of the core support up top. Under the snorkel.Looks like it could possibly be an air guide to stop air from escaping the shroud, maybe between the core support & radiator if that rings a bell for you? There's a lot of.these little tricks they use to keep the air going where they want it.
Yep. Thats it.Ah, I think I see it ! :
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