Hi All! Newbie to tartan etiquette here.

I've been invited to an event in Scotland for next year and one of the dinners has been labeled Black Tie with Kilts (for the guys) for the dress code. I've got a good idea of what normally Black Tie for ladies would constitute, so here's my question:

Would it be inappropriate for me to show in a hostess-length tartan skirt, appropriate top, heels and matching sash? Or would it be more appropriate to wear a modern evening gown with a tartan sash?

While the event will be at a large castle estate and very formal, it's doubtful that any sort of royalty would be there, although you never know.

Thank you!