Originally Posted By 6bblgt
Originally Posted By John_Kunkel

MN42630035319

MN= Plant identifier for the Marysville engine plant
426= Displacement
3003= Build date October 17, 1969
53193= Sequence number


there's a fifth digit to the sequence number for 1970 model year & it is/was a hemi'cuda drive



So the 3 after the sequence number means 'Cuda? I did not know that. I've never seen any info on decoding the sequence numbers.