They probably could, but most service managers weren't going to. Keep in mind that the engine replacement would have been covered under the new vehicle warranty. The fact that a part was replaced under a factory warranty meant that the part was good for the remander of that warranty, or 12 months, 12,000 miles if it was replaced with less than the actual warranty on the part. There wasn't a huge need to document on the POP the actual numbers, since that replaced part carried the remainder of that warranty. Today if a part is covered under warranty then it will carry the remainder of the 3/36k. However if the part is replaced at 35999 it would have a 1 year or 12,000 warranty, which can go outside of the 3/36k factory warranty. Sort of complicated hmm..??