M1 Single Plane Thermostat Housing

Mad Dart said
Tracy,

I am pretty sure you are correct, kind of weird I had the heads dual drilled for the LA intake and I have to use Magnum Intake bolts and Water neck set up on it........weird!!

Yeah that is odd. Probably something stupid that came about when Daimler owned Mopar. I know the older M1's weren't that way.