[Gerard Auckram]

Using chat GPT:

Breaking Down "1MTWS1"
1M – Indicates a Mercury or Ford truck engine, commonly used in Canadian-built vehicles.
T – Typically stands for Truck application.
WS – Possibly refers to a casting location or production variation.
1 – Could indicate a revision or casting batch number.
Possible Identification:
Likely a Canadian-built Mercury flathead V8, possibly the 255 cu in (4.2L) version used in post-war trucks.
Related to the 8RT or 8CM engines, used in 1948–1953 Mercury trucks or heavy-duty Ford trucks.
If it has 24 studs on the cylinder heads, it’s a later flathead (1948–1953).
How to Confirm?
Check the stroke:
255 cu in Mercury engine → 4.00-inch stroke
239 cu in Ford engine → 3.75-inch stroke
Look for additional casting marks on the intake deck or bellhousing area.