What window channel are you looking for?
Are you talking about the channels that the glass sets in or the "fuzzies" that the glass rides into? If it is the fuzzies, then large glass shops will have catalogs where you can all different sizes in 5-6' lengths and you can make your own.
I need this part.
I looked up 62 Biscayne and the glass looks the same for sedans.
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