Ls6 CRV block

[XXXGoldL34M20]

Did you check the pad near the oil filter boss to see if there was a Vin number there? 1970 Van Nuys would stamp the partial VIN on the rough cast area by the oil filter. see photo

Also I'm not real surprised by the date spread you have as this happened once in awhile with blocks sitting at the back of the batch of the newer made blocks, it was not common but it did happen as there are a few survivors documented with longer spread dates than others [img]<<GRAEMLIN_URL>>/biggthumpup.gif[/img]