There are no rocker assemblies that span that many years.
1954-58, and 1959-62 for complete assemblies is correct.
1954-58 rockers have a groove inside each rocker that is centered. 1959-62 the groove is offset 1/4" from center.
If you use the rockers with centered grooves on 1959-62 engines you will get to much oil out of the vent holes on each rockers.
This can be over come easily if needed.


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