Howdy Finn,!
On my TD when I had aluminum under where my diamond plate would go I used rivets to attach. I also siliconed with silicone formulated for alluminum for extra bond.
When my diamond plating didn't have alluminum under it I used screws. I also used screws on the tighter curves as the rivets didn't hold down the DP as good as I wanted.
Srry i'm not a technical type guy and I'm not good at explaining how I do things.
I also used screws to even out the looks if that makes sense. I tried my best to keep them evenly spaced and straight. I have a lot more screws than needed but to make the screws more appeasing to the eye I put more in certian place to balance the look.
This piece is on the hatch but it's the same on the front. Across the top you can see the screws. There was too much of a bend and the rivets did not work as well as I wanted so it's screwed. I really didn't mind the look of the screws.
Hope this helps and I'm sure others will chime in soon.
Ken.
Your TD is looking really nice!