Did you apply before or after full detail on car?
At the time, I applied to all plastic trim after complete wash, Iron-X Decon, Clay, a full 2 step correction with WG TSR and WG Finishing Glaze with the PC DA, WGDGPS 3.0.
I then did the coating on all the Plastic Trim the next day (except wiper cowl) while I was nice and fresh, the vehicle was covered overnight with a Covercraft Cover..
Just simply had to then wipe all trim that was going to get the DLX with a MF Towel. I did mask critical trim, such as all the rubber-plastic around all windows, there was nothing that wasn't coated except the metal black powder coated roof rack. (That I did a year later with CQ UK)
The DLX was truly the icing on the cake. Everything, except the Wiper Cowl looked brand new, and glowed. The next week I yanked entire Cowl and did it as well.
Being a finned Cowl, and about 6 feet of it in 3 pieces, this was going to be a real PITA by MF Suede Applicator, and pretty much had no choice but to dribble DLX as I went onto the part, then spread with a soft 1/2" Wide Artist's Brush.
Yep, I went through a lot of extra DLX that way, but was sure a lot simpler-easier on me doing it this way. Had the entire Cowl coated in about 10 minutes or so, then didn't touch it, let the product dry fully overnight, the next day I re-installed it on the truck.
The cowl is the hardest thing to keep nice on this truck because of the dumb raised fins they put on it.