weird engine manufacture code

[70CitrusZ]

Its an L36 4 spd car built in St.Therese.

I should have double checked things before I posted...because now that you guys made me re-check the docs, its engine code indeed starts with a "T", but the code ends with an "S". The engine is at the farm, so I can't double check the stamping, but the engine code on the docs is T12223S which seems odd to me that it would have a one digit engine code. Obviously the engine plant is Tonawanda, which now makes more sense.
I still don't understand the single "s" engine code.
maybe I'll have to wait until I get to the engine to verify that this code supplied by GM is complete.

And yes I did get the engine code confirmation with my GM Canada docs, although on other cars I have documented there has not always been.

The build date of the car was April 26, 1968.