Well since most of the 428 blocks carry a C6AE-.....casting number you can ID by date code. Also PI and CJ blocks have the triple webbing on the crank saddles. Heads and intake,carb,crank,rods etc... can be ID by casting numbers. The 428 cobrajet registry has an excellent section on parts ID with photos and casting numbers.
www.428cobrajet.org Take a look. Hope the link is correct. Glenn.