I also just installed the electric wiper motor in my '53, and like yours my driver's side does not sweep the entire glass, only about three fourths. Mine does however go beyond the straight up point. I think it is largely the nature of the original wiper mechanism having one long arm and one very short arm. You might check to see if the short arm is bent a little as a small bend would limit its travel. Also I set my drivers side to park a tad higher, which adds some travel. As a last resort it might be possible to rotate the motor a small amount to gain some wiper travel.
RdsLessTaken/Don

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