Dart GTS Custom sill moldings question

Ok. Good info HemiSS.
I wrote it down when I saw it listed as "custom sill molding" and thought it was odd. Maybe it was called "custom" because it was optional on all other darts? Idk.
I do have that thinner molding but need to figure out how they mounted it. My guess is they used clips and 1 screw from underneath in the front?