It seems like the AOS should be easy to change at that point since it is also in the same general area. So he shouldn't be charging regular labor rate for the full job when most, if not almost all of it, will be right there.View attachment 281746
The part in the yellow box ("B" in your photo) above is the balance pipe to help balance out the two intake manifolds. It may also do some tuning of the manifolds by opening/closing a vacuum controlled valve. The blue/green box is where the vacuum actuator lives, on the side of the balance pipe. There is likely a flap type valve inside the balance pipe - and it sounds as if that and/or the vacuum actuator is broken.
it sounds as if he's removing the entire intake manifold since he lists 6 intake manifold gaskets (1 for each cylinder), this might be needed if he suspects any broken bits have gotten into the intake manifold itself. Then it sounds as if he's just going to replace the vacuum actuator.
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