Did your 66 have the oval speaker cover that goes over the back of the speaker? I have found one, and repaired it and installed it, not the best but better than the gaping speaker hole in the rear of the seat! At least I think so. It is a really flimsy plastic job, but I am told it is correct. Been trying to find a photo of what really covered the rear speaker originally in a 67 drop top, but it seems that everyone breaks the one they have, or had! Not surprising given the brittleness of that thin plastic. Love that year of convertible!
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