“D” code 340 in 69’ Cuda?

THere is no numbers on or near the bellhousing...

The engine factory information is stamped on the front of the block just under the driver's head...

The VIN of the vehicle is stamped on the flat spot on the front of the block on the passenger side just above the oil pan....

If you take a gander at a couple of pics I’ve posted you will see that there is no machined pad near the oil pan the only numbers that have been stamped are the ones near the head nowhere else