FOUND 70 340
OK, it is a new number to me, but it is from a 1970 Cuda. So there are only two possible VINs for the car it came from, I'll list them both here just in case the car owner Google's his VIN;
BS23H0B207773 or BS27H0B207773
I noted the block in the 1970 Hamtramck Registry database, so if I hear from the car's owner I can have him contact you.
Thanks for reporting it!