The 58-64 Chevrolet full size, and Pontiac "7000" series were built on the same assembly line in Oshawa, Ontario. All the 63-65 Canadian built cars that were fortunate enough to have been delivered with a 409 ( there were no 61/62 Canadian 409 cars ), had the completed long block imported from the Tonawanda plant. These all carry the same engine number sequence as the 409's that went into U.S. built cars. There were no vehicle serial numbers stamped on ANY of them.
Now, the 348 ?
Wish I could tell for sure.
The stamp number on the pad of a 348 that was in any Canadian built car, 58-61, is a COMPLETELY DIFFERENT animal from the 348's in the U.S. cars.... COMPLETELY.
There is no "H" code, ect.
Typically, the Canadian 348 has a "9D", followed by 4 numbers.
I can't for the life of me, figure out what it means. Were they actually cast and assembled in Canada ? Were they maybe just assembled in Canada ? Or were they shipped from Tonawanda with no stamp on them ?
I have no idea
One final note...
In Canada, there were only the low compression ( 9.5:1 ) 348's available in cars... 250 horse, or the triple 2 bbl 280 horse.
No high compression, no mechanical cams, no aliuminum intakes, no 2 1/2" exhaust manifolds, no "1147" heads.
Hope this was of SOME help