You might have better luck posting in the Windsor Power forum but I don't think the cover should be too hard to find. If your local junkyards don't have what you need, I think i've seen them listed in MustangsUnlimited. I could be wrong but i'm pretty sure one of the catalogs can hook you up.
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66 Tahoe Turquoise Coupe
Laser Red 96GT Ragtop
Both are slow but easy on the eyes!