I have the same issue - definitely more of an annoyance. I have an appointment at the dealer on Friday for an unrelated issue and will bring it up. Once I noticed it, I could not unsee it.Update: so the dealer grab the same piece from an unsold Integra and it fit MUCH better. Still a small gap, but the others on the lot they had also have a gap.
The NSX tech believes it’s the material and how it’s bunched up and stapled in on the underside. It was very bunchie in that spot and could have stopped it from sitting tighter.
Oddly enough, my old piece fit snug in the other Integra.