There's both horizontal and vertical adjustment. There are two E-8 (IIRC) Torx screws (6-point star shaped) on top of the headlight.

This is how mine were shipped to me. You can see how the horizontal alignment is maxed out in this picture. That will result in the huge gaps you describe.

Any time you get new headlights, you want to aim them. You can attempt it yourself (it's a lot easier on projectors because of the sharp cutoff), but it's probably better to take it to a shop.