NEED HELP WITH DATE CODE ON SPARE WHEEL??

I have a wheel that was a spare in one of my cars and I need help decoding the date on it. Here is what it is A1-8 2 (valve stem) Y9 55. I am not sure on the first 2 characters due to a weak stamp. If you can decode this for me I would appreciate it.
John

Probably...
M1 or K1 = Wheel Plant
8 = 1968
2 = February
19 or 29 = Day of month
5.5 = 5.5" wheel width

It's also likely you could find the month & year stampings elsewhere on the wheel, such as inboard side of the center between lug holes and/or on the tire side of the "hoop".

Rick