I don't remember the instructions stating which is taxi and landing but the outboard lights can be aimed inward to cover more of the area directly in front of the aircraft so I used those as taxi. The inboard are limited to vertical aiming because the wingtip cutouts block more of the horizontal light.
Of course you can use all of them for landing but in a taildragger, once the tail drops one set will be aiming more upward than the other. On a nose dragger not such an issue.
