273 dilemma

fireguyfire said
I have with the 273 commando engine that is matching numbers in my 67 formula S

fireguyfire said
but am having zero luck as I would love to save the matching numbers engine

Sorry to be that guy but....

There is nothing on the engine that ties it to the car except the engine build date being days to weeks before the car assy date.

Any 273 with a build date in the range will be undetectable as not being the OE engine. You will know but that is it

My 67 dart has the OE engine and was rebuilt once. But if it can't be bored again any engine built in the last quarter of 66 will work