Rebuilding heater box, replace core?
Seals from DMT. The ones with arrows are the ones that I determined might be used on a '67.
Cardboard is a little thicker than original but cut is perfect match and fit is good.
The circular tan gasket is in case you remove the motor from its attachment plate as Dana shows in different thread.
As mentioned in the previous post, the original temperature control door seals
may have been a thicker yellow open cell foam.