We have a 67 Mercury Cougar with a 289, but we are not totally sure that it is the original engine. We have no idea where the FoMoCo small blocks put the block casting numbers. If we can find the numbers, we can see if it is the original engine and decide whether to do a full restoration or to customize the car.

Casting numbers will be on the lower block. If it is the origanal engine the vin will tell the casting number possibly.

On the passenger side of the block, just above the starter. It is usually very tough to make out without removing the starter. It should start out with something like ''C7AE-...'' or something similar.

Gypsy R is right. There is also a # in the valley under the intake, & l think, there is one on the back wall behind the flywheel.