Here is a sketch I made several years ago when working on Dad's 77. This sketch doesn't show ALL of the factory hole locations because we chose to substitute extra plastic stick-on clips in many locations (especially on the front fenders) to reduce the number of holes we had to drill into the new body panels.
Since your other front fender is original with the holes, you should be able to measure the hole locations off that and mirror them over to the replacement fender.
The tailgate trim is the same upper & lower. The lower one is oriented with the accent stripe near the top and the upper one is flipped around with the accent stripe near the bottom. Both were attached from the factory with several plastic stick-on clips along the center. And if I remember correctly, the outer ends of the lower piece were secured with metal snap-in clips while the outer ends of the upper piece used metal clips with studs on them and were secured with nuts (accessible with the tailgate open).