[HWYSTR455]

Don't believe that answers the actual question by the OP.

Some cars did have a drain hole in the lower corners with a drain tube that ran into the trunk drop-off, and drained out the groove of the body panel plug hole.

But no 64-72 GM car that I know of used that 'feature'.

I believe it was abandoned due to the fact the drain hole/area would build up with debris too easily. But this is just a 'theory'.



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