Seattle,
Its now 2024 and I am in the exact same boat as you. I even called Mancini BEFOREHAND advising of your MC missing the retainer groove and the guy said it was probably a manufacturer defect and all the new ones were “fine”. Nope. Mine was exactly like yours. No groove. So Ill be sending it back. My question is can you advise what Napa MC you got instead?
Thanks!!
Thanquol in Wisconsin
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