weird engine manufacture code

[70CitrusZ]

I wonder.. could it not have been the assembly plant that hammered in the engine app. code? maybe the T1222 was on it when shipped to St. Therese from Tonawanda, and they added the 3S application code at Therese? The "S" could be for St.Therese, and the 3? maybe the 3rd engine used?? or 3 for the application or usage?
I asked George if he could elaborate on the odd engine number and he said he couldn't.
I can't imagine they had too many of these engines in the plant, as only 25 of these cars were built in Canada.
Does anyone else on the site have one of these cars? maybe thier engine number is similar...