If I'm right, the VIN tag is stamped by the manufacturer.
If the tag doesn't have H54 then either there was a tag swap or a cab swap.
Mr. Moderator, we may need to stop discussion until the OP can verify if it's legit.


"Adding CFM to a truck will only help at engine speeds you don't want to use."
"I found there was nothing to gain beyond 400 CFM."