So if you are using the new magnesium manifold chances are you need to port the manifold to have it gasket match. You will need a 1-2mm increase.
Now why did I post this? Well I been getting a lot of request for PnP for people who wanted to gasket match the runners to the 3.7L manifold. But I am sure that the manifold also needs to be Ported to match the increase diameter of the runners. If anyone wants to measure the opening of the manifold to confirm this please post pictures
Using p2r gasket as reference probably not the best idea since they do deform over time
Also don't ask if the gen 8 runners fit the gen7 runner!!! Just look at it!
Last note. Do not gasket match the side going to the head unless u also plan to match the head. I have gasket match TLS heads so it was okay for me to do so beacuase it presevers the flow and will not increase turbulence due to a lip on the head side