Cowl (sealing)
An inovative thread a few yrs ago, had a liberal amt of Por 15, poured down the outer grill,, he jacked the opposite side of car fairly high, and left to set,,
I can't remember if he jacked before or after adding the Por 15 ..,
the Por 15 apparently ran around the duct and sealed it... always thought I'd try that if I got a "leaker"..
hope it helps