I have a 73 with a head # FF 015 MCT. Any decoding available?

It should be marked E-88

It's stamped into a machined pad on the valve cover rail by the thermostat.

I'd post a pic but the image is too large and my photoshop is kaput. E88 is cast on the head.

Trying to attach a pic

Must admit it does look like a serial number, rather than a head model (type) number. Never noticed it before.

Is it a number left behind by a rebuilt shop, or maybe a stamped replacement part number?

I'm no expert, but I was under the impression (from the countless threads on Head castings) that the heads themselves bore no discernable serial numbers.

My 72 which I know is original is stamped FF-SP. Look at yours and post the number.

I'd never noticed this stamp before. It's hard to see with the valve cover, fuel lines, and air injector tubes in the way. Mine actually has two different stamps, one near the front and one near the rear of the head. Mine doesn't even have a number but does have the same crooked FF and a G at the end but no numbers in between.

Your right. My 72 is stamped D 2 on the rear pad and the 73 shows Z 3. The plot thickens.