For Ford era Panteras like mine, there is a number stamped on the engine block just below the head on the left hand side of the engine (visible with the heads on), when you are looking into the engine bay from the back of the car.
Mine doesn't have this number on the engine, therefore I know it is not the original block. There is a tag on the chassis on the left hand side in the engine bay, if you panned slightly left in your photo, you would see it on a Ford era Pantera, and it may be in the front trunk area near where the chassis number is stamped in. There are some good pictures and description on the Provamo homepage: http://www.provamo.com/Members...chingMotorNumber.asp
But, as I mentioned, I don't know if all this is valid for a 9000 series Pantera, maybe someone else can answer that.