I bought the plastic clips and did not like them because I felt that they would not hold the trim securely enough and after any paint build up could cause fitting issues. I only needed to put the passenger side rear trim on from the door back to the rear light. This was because that rear quarter panel had been replaced with an Alpine panel because a teenage run into it way back and the trim was never put back on The Alpine does not have the trim. Since I had all the interior panels off from inside the trunk and the rest of the car I could reach inside the compartments to where the clips would be located ( I did have to drill the holes for the screws I used) Instead of the clips I found that brass round head screws will slide into the stainless trim grooves and then secured them with nuts. I don’t remember what size screws I used probably number 4 or 6 that were 1/2 inch long There was one which took a lot of fiddling to get the nut on I think there are 6 or 7 for that strip Brass won’t rust if it gets wet from rain or washing. I have original paint on the car and will leave it that way so the other strips are not going to be removed.
I have heard that body skim coat and paint build up has been a problem when the trim is put on after if the holes have closed up. And the thickness of the skim coat and paint makes fitting of the clips and trim an issue.I would recommend trying screws.
Good luck