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As current '69 'Velle thread, some factory GM info noted Copo 9511 necessary to get 4:56 or 4:88 for 1969 cars only....all models.
Even though 9511 not noted w/ this L88's paperwork, the M22 may be specific to suit rear also the 9511 may've shown if 4:56 part was printed info, not added w/ pen?
~ Pete
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