When doing a fresh piece of carbon fibre for your kit. Always chamfer all of the holes that are a sharp edge. I see so many people who don't do this and when they nip the top deck down it adds tweek to the chassis because the screw can't sit flat. This is proven by the silver ring you can get around all the holes hey. Doing this also means your less lightly to get tweek in a small dink (I do those alot). This is also the same for all the bulkhead as all will have a small radius on them. It takes 10 secs to do the kit but saves a season of irritation.

So in picture 1 you can see the radius under the face of the head.

Picture 2 shows a small chamfer dressed onto the top deck so the head of the screw can clamp flat onto the top deck and not the radius of the screw.

When you put new hexes onto your car or even just swapping, before you do up the screw to clamp it onto the pin put your setup nuts on and nip them up so the axle is pulled tight up to the bearing then nip the small screw up. Then any bruising through use will be in the best position and help the hex to be seated tight up to the bearing.

Any blank holes in the rear hubs fill them with a vrub screw so if you do have an impact it has less chance of flexing the plastic and pulling the ball stud out.