djpritchard1: Look under the starter. There is a pad on teh block that is lengthwise to the oilpan. Should start with C6OE or D2AE or something similiar. (different codes for different years) Get me those numbers and I may be able to decode it for ya.

froggy: I believe the 429's block Id is in the same place as described above and in the same fashion. On the heads though the casting # is casted on the top of one of the exhaust protrusions where the exh manifold bolts to the head. (or right in that area) Casting numbers will be similiar as listed above.