I'm a new van-er, but I'm a VW guy, and familiar with the decklid space-out trick as well. I did a similar thing on a few of my Toyota rockcrawlers, because you have very low speeds and high loads. I used spacers at the hinge bolts, spacing up the back of the hood, giving another exit for heat while moving slow or parked - reduced vapor lock quite a bit on one of them. At speed it allowed cool air in, like cowl induction. I think the vents can only help. Any concern about water entry?
Classic European Cars and Parts
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