May as well keep the individual topics going. Maybe should have just logged as a 3800sc refresher or ...
So the lower intake gasket has been replaced. While positioning the center dams, the plastic pins did not line up with the block's holes; they were too close center-to-cente by 3mm which was just enough not to fit. Wondering if there were variations within the II-series block, or just poor OEM quality. I used the aluminum gasket set from GM. I ended up eliminating the plastic pins from the dams and positioned them time and time again to ensure that once I placed the manifold, they would stay in position. The passenger-side is visually available but the driver-side is not.
Fingers crossed that it held it's position - yes, I used RTV in the corners
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