1967 & 1968 C50 share the same cabs. However; they differ from the smaller p/u trucks of those years. If memory serves right, the doors are the same as the p/u's for those years w/ the only difference being is the angle cut your doors have. You could swap out for the p/u doors if you cut & weld (the angle) to match your doors. As far as internals within the doors go, I believe they're the same (p/u & C50). Hopefully someone here will chime in to confirm this.

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