1965 MOPAR, 273 Exhaust Maifolds

The ports will match up just fine, however-
If the heads are '73 ish or earlier, and have this shape pad around the ports, you will be fine.
View attachment 1716176166
But if you've got '74/'75 ish or later heads with the extended pads (made for air injection, may be drilled or may not, needs to be plugged if it is), like this:
View attachment 1716176169
Then there will be interference between the bottom portion of the exhaust pad on #7 and the downleg of the exhaust manifold, which will not allow you to tighten down the manifold to the head.
The amount of interference varies due to manufacturing tolerances, sometimes you can get away by double gasketing the manifold, sometimes you have to use a spacer, normally a header flange, to gain the needed clearance.
View attachment 1716176173
Some say that they have been able to grind enough of the offending pad to get it to fit, but I have personally hit the water jacket just under the surface with minimal grinding- up to you if you want to take that chance and trash a head. Even if you don't hit the jacket, how thin is the metal that's left? I play it safe now and just use the spacer.
But as I previously said, if you have the earlier heads, it's no problem.
Edit: Just to clarify, to my knowledge this is only an issue with the (early) A body manifold, and only on the driver's side.


It may not matter about the air port plugs with the early style exhaust manifolds.. They may not go that far down for any interference, he would just have to plug the holes to prevent an exhaust link...

The early exhaust manifolds (I believe 64 - 71 series) don't extend down far enough to interfere with the exhaust port on the head where the plug would be... The later model exhaust manifolds do...