The tag will break down as follows:
1st Digit is the YEAR
2nd & 3rd Digit is the MONTH
4th Digit matches 7th Digit of the VIN (engine size)*
5th & 6th Digits match DAY OF MONTH engine built
FIRST DIGIT is YEAR
1=1968; 2=1969; 3=1970; 4=1971; 5=1972; 6=1973; 7=1974
Other early years:
1=1959; 2=1960; 3=1961; 4=1962; 5=1963; 6=1964; 7=1965; 8=1966; 9=1967
Other later years:
8=1975; 9=1976; 1=1977; 2=1978; 3=1979; 0=1980
Final end run years:
1=1981 VIN Code B; 2=1982 VIN Code C; 3=1983 VIN Code D; 4=1984 VIN Code E
5=1985 VIN Code F; 6=1986 VIN Code G; 7=1987 VIN Code H; 8=1988 VIN Code J
It looks like the valve cover was changed at some point. 611H16 would decode as follows:
6 = 1973
11 = November
H = 2BBL 304 (1970-1979)
16 = day of month
So your valve cover came from a 2BBL 304 manufactured November 16, 1973.
Info from here: http://www.planethoustonamx.com/ Go to the "production/tech" tab on the left.
Bob
tufcj
