Hi, Pete - These numbers work together fine. The car # 14JKA29716 says the car was built in Baltimore (14...) and is a 1951 Series 2100 (..JK..) "Passenger car, Deluxe, Styleline or Fleetline" and was built in January 1951 (...A). The 29716 is the sequential build number.
On the engine, JAD is a 1951 235" with Powerglide in a Passenger car.
I see where the Old Car Manual website shows JAD as ??? - but I have a page saved in my computer from an old Chilton's book (I think) which lists out ALL the various prefixes and suffixes, and it shows the JAD as specified above. I'll try to post a scan of the page, look in the left column, toward the bottom where 1951 entries start, the 6th entry under the 1951 codes.
The sequential body number and the sequential engine number would not necessarily match on a car in this era, like the more modern cars for "numbers matching." This combination you identified could well be born together, especially if the engine Casting Date is in January 1951. That Casting Number is probably hidden behind the starter.