Bend more arch back into them. That is the spring that keeps tension on the gasket without putting all the force on the somewhat weak engine cover.
Or try a new gasket. If you push forward on the engine cover and your noise gets lessened, bend the latches a little, if goes away your done, if not get the gasket.
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2002 e350 window eb,
7.3
CCV high top
Conversion in process. Lol
Denver, CO