Filling Trim Holes, 69 Dart

Hey guys, need some help.
I'm having a hard time finding all the correct trim to fill the trim holes on my dart and I was thinking of just filling the holes, but wanted to know what the best way to go about this would be?

I was told if I welded them, that I am going to have to skim the entire panels because the trim holes are on a small body line that will begin to warp