Is there anything stamped on the vin pad? There is also mention in the Mopar Performance racing manual of a PN-3690030 block that was cast for Grand National use after the Hemi was dropped. The only problem to identifying this block is to find someone alive with a memory and a working knowledge of it. Also notice the reinforcing on the lifter bores. I acquired 1 of these blocks this summer and still have no definitive answer.
Randy