Look in the Assembly Manual, UPC 12, sheets A2 and A3; in order to re-position the buckets in the openings (to adjust the gaps), you need to loosen the three attaching bolts for the housings (items #5 and #41), move the housings slightly to achieve the gap you want, and tighten them again. This requires removing the headlight motors, and removing the headlight bezels and the headlights from the buckets so you can get to the three access holes in each end of the buckets so you can get a socket on the three bolt heads for each housing.
The rotational movement of the buckets (for flush adjustment to the front surround panel), there are Y-stops with bolts on each leg on the inboard end of the pivot shafts, adjacent to the motors.