I recently removed the heads on my 73 302. There was no indication that the heads had ever been off but the head gaskets were McCord brand and had no Ford part numbers. Did Ford use this brand at the factory or is this an aftermarket set?
I'm not sure about McCord but someone had to make gaskets for Ford, GM etc. I know it was common to find Victor gaskets in Ford engines. Suppliers that sell parts commonly found in aftermarket, often supply OEM as well.
I think Ford may have used some McCords but these probably are aftermarket. At first I thought the heads had never been off but upon closer examination it is now obvious the car had a valve job at some point. At least one intake valve had been replaced. At any rate it has Fel-pro head gaskets on it now.