Just went through the same. I could not get the intake between the heads.

I wound up putting extra head gaskets on until I got the intake to fit. Once I knew the deck increase needed to make it fit, I calculated the intake cut.

So in my case, it took two extra gaskets .040 (each), .080 total to make it fit without a gasket. I took the .080 x 1.23 to get .0984 or basically .100. I wanted to use a .060 intake gasket, so by the math I needed .160 total-I decided to just go .150. Since the heads had been milled and the intake side had never been cut, I cut the intake side of the head .050, and then I cut the intake itself .100.

Everything fit perfectly with the gasket after the cut. All the bolts run in by hand.


'75 Plymouth Duster
Phase I 451 906/590/2-660 10.75/126
Phase II 451 Stage VI/590/1050 9.82/135
Phase III 383 906/Victor-Pump gas 11.30/119

"For by grace you have been saved through faith. And this is not your own doing; it is the gift of God,"