how should I check for the correct thickness intake gasket needed?feeler gages under the intake?
how would you do it?

I stacked some cardboard and bolted down the intake to be even all around and used feeler gages to check all corners and I need .160 thick gasket or spacer with gasket so it looks like I need to make a .100 spacer from aluminum and port match it.

OK thanks!The .004 sounds like a lot of taper though,I would think .001/2 would be enough to be sure it seals all the way around well. I will have to wait to do a more accurate measurement when the heads get torqued down. I have some .080 aluminum I am making a spacer from and port matching to use if needed later for mockup or otherwise.Thank you.

I have to fine tune the port size and bolt holes but not too bad.

Nice work Mike

Here's mine with a .031" gasket between the plate and the head.

I used slotted roll pins pressed in the heads to locate the plate to the head (Red) then I port matched it.

The (Blue) circles are the holes I drilled through the intake manifold into the plate to locate the manifold alignment with 1/16" solid pins that are removed when I snug the intake down.

Whenever I have to pull the intake I know that when it's reinstalled everything goes back in EXACTLY the same position

Thanks Greg those assembly tip will help down the line forsure.I can align the ports,gaskets through the intake with my fingers so I won't be doing it blind but will eventualy do as you have.