Most likely on the pad.
In the 1969 model year, the partial VIN for V8 engines was stamped in either of two locations: on the engine pad or near the oil filter. The alternator was moved to the passenger side in 1969 which covered the engine stamp pad and caused the VIN stamp to be relocated by the oil filter. The block in this area is raw unmachined casting which makes this stamp difficult to see. The Norwood plant stamped the VIN on the engine pad on early cars and moved the stamp by the oil filter in the December 68 timeframe. Los Angeles was not as consistent and the VIN stamp location varied during the year.