| 1925 |
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| 1926 | |
| 1927 |
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1928 weight class 1 note: only year with weight class, only year with "TRAIL" legend |
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1928 weight class 2 |
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1928 weight class 3 |
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1928 weight class 4 |
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1928 weight class 5 |
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| 1929 |
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| 1930 | |
| 1931 | |
| 1932 | |
| 1933 | |
| 1934 | |
| 1935 |
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| 1936 |
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| 1937 |
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| 1938 |
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| 1939 |
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| 1940 |
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| 1941 | |
| 1942 |
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| 1943 (tab) |
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| 1944 (tab) | |
| 1945 |
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| 1946 |
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| 1947 |
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| 1948 |
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| 1949 |
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| 1950 |
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| 1951 | |
| 1952 |
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| 1953 |
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| 1954 |
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| 1955 |
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| 1956 type 1 |
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| 1956 type2 |
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| 1957 |
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| 1958 |
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| 1959 |
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| 1960 |
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| 1961 |
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| 1962 (early) |
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| 1962 (late) |
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| 1963 |
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| 1964 |
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| 1965 |
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| 1966 |
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| 1967 |
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| 1968 |
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| 1969 |
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| 1970 |
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| 1971 |
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| 1972 |
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| 1973 |
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| 1974 |
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1974 |
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1975 |
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1976-85 letter prefix |
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| letter suffix |
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| 1985-87 sesqui. format |
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| 1987-2001? small TEXAS format |
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| 2001?-2003 large TEXAS format |
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| 2003-pres. |
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copyright 2004 to 2008 Nick DiFonzo