I have 2 original Delco master cylinder lids, one from an early (dated 1339), the other from a later (June 70) build.
There are slight differences in the 2 lids and wonder if it IS an early VS late thing, or just supplier variances.
I do know that the very early `70 Chevelles got the `69 style disc brake master, but obviously these are from the rectangular design.
Center bar differences.
Font and shape differences.
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Rick
69 Chevelle SS396 Silver L78 M21 Post Sedan (Berger Chev.)
69 Chevelle SS396 Black L78 4-speed 4.10 Post Sedan
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