best guess from examples shown:

054 0 2 KH 80012 28
054 0 = assembly date - 054th day of 1970 - Monday, February 23, 1970
2 = 2nd shift
KH = Kelsey Hayes
80012 = casting number
28 = casting date - 28th day of ? - Wednesday, January 28, 1970

049 0 2 KH 80012 353
049 0 = assembly date - 049th day of 1970 - Wednesday, February 18, 1970
2 = 2nd shift
KH = Kelsey Hayes
80012 = casting number
353 = casting date - 353rd day of ? - Friday, December 19, 1969

210 9 2
210 9 = assembly date - 210th day of 1969 - Tuesday, July 29, 1969
2 = 2nd shift