Need help.

I have a 225 slant six in my 72 duster. There was some rigged up piece of crap throttle bracket on it. I got an original bracket and installed it. Now I need to know what is supposed to cover this hole in the side of the exhaust manifold right about the throttle bracket with the 2 studs.? The old rigged bracket used to cover it up.? Any help will is greatly appreciated.

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