Yes, on my helmet, the right jaw line was the longer side.
No, I did not move the guide holes for mounting the faceplate. Everything (aside from the right jaw line) lined up when I tested the fit of the faceplate to the helmet. When in the closed position, there is a gap of approximately 1/4" between the faceplate and the matching contours on the helmet. This allows for the faceplate to open, something that I don't think would be possible if the faceplate mated perfectly to the contours on the helmet.