It would not be uncommon to have a truck in which the block had
been replaced with a new one from the factory. Could have
burned it up from heavy use or abuse, cracked the block by not
keeping antifreeze in it. It would have been delivered without
a SN and the installer would have been expected to transfer the
SN from the original engine to the new short block or fitted block.

Denny G


Denny G
Sandwich, IL