The Sonoramic Commando Intake?

2 Darts said
IIRC, the long ram was available in 1960-61. That would mean that they would only fit the RB version of the 383. There is no issue with the 413 because it was always a RB engine.
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No.
The long ram intakes (with either long or short internals, '60-'64) are the only intakes that fit both B and RB engines.