Fitting stock plastic decklid grille to SC. Is trimming required?

[ASTAR911]

I am in the process of fitting a plain decklid and notice that the plastic grille will not fit without trimming part of the underside.

I did a search and notice on old posts that some appear to have been trimmed and some appear to fit perfectly!

What is correct? Do I need to trim the top triangle bits slightly for a perfect fit?

I have attached some photos for reference. The first photo has the plastic grille trimmed around the top three triangular parts of the decklid and the other appears to fit perfectly without trimming.