Header Gaskets....

Those are both for later Magnum 318's. Take a closer look at this page and be sure of what you actually have in your car. If it's a '65 273 then you need the 6016.

Remflex Chrysler page 2: V8
My bad. Engine is an '87 318 and will use EQ heads which I thought had the late model Exhaust port. I did not see anything specific for those heads.
Bob