doyle1950, I think you have it pegged as a Canadian 261. Lots of info in a couple of previous threads on this engine Engine Code starting with "W" and Canadian 'Poncho' Rebuild.

The same block casting number 3836340 was used on both US and Canadian 261 from 1955-62 as referenced in Bolter tclederman's Stovebolt Casting Numbers webpage and many other resources.

Sounds like your truck is in for a big step up in the powertrain! grin


~ Dan
1951 Chevy 3 window 3100
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