To : Blackbee
From the number you've posted;
Engine Assembly Number - T0405DTW
Partial Engine VIN - 19K551101
We can determine;
Engine Assembly Number - T0405DTW; T = Tonawanda (assembly plant), 04 - April, 05 - 5th (day of April), DTW = Engine Suffix Code, a little trouble here, I checked several data bases and did not find the DTW Engine Suffix Code listed, I did find an Engine Suffix Code DWT, here's the info on it, 1983, 305 cid, TBI, 165 hp, Firebird.
Partial Engine VIN - 19K551101 - 1 = Chevy, 9 = 1979, K = St Catherines, Ontario (McKinnon Industries Canada) (assembly plant), 551101 = matches VIN Serial Number.
So, this one is a little peculiar!
The discrepancy is based in the Engine Suffix Code, it would be helpful if you could double check it, to be sure there isn't a typo in the code.
I am hopeful some of this is helpful!