New style manifolds comes with gasket-side made of bronze, rather than the older plastic types that leaked. This is the side where the barrel unions screw into the manifold. Older manifolds had a plastic face-place. This retrofits the older parts.
When replacing, make sure ALL rust in removed on heat exchanger plate. A good Sealant (not silicone!) may need to be used to fill gaps. Use a sealant such as Permatex Copper found here.
This kit comes complete also with 9x new tube seal gaskets
Some parts from the original manifold will need to be swapped onto new manifold.
Comes with all parts in diagram below as highlighted.