First, I hear the exhaust crossover can be blocked off to prevent paint burn on the intake. Being on a boat, I dont think I need to worry about warming up the intake? If it can be blocked, what is the best way to do this?

Second, The intake has a "mushroom looking appendige" on the left side of it...looks like some kind of a vent. What doesit do? Does it have to be there?  Can it be removed and plugged?

Here is a pic I found of one like mine that shows what Im talking about .....

Thanks!

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