Good afternoon, Kendo,
9ac is an anagram of 5d. (3) + s + hair.
If you put it before 27ac., it gives you an actor.
It also fits in with the theme of several clues.
Good afternoon, Claudie.
1ac - ivy is a type of this, I suppose, and it's a synonym for a sleeve in an engine. The answer also fits the theme of various others.
2d. Think small, onion-like, bulbs - or a poetic Lady!
Hoping this jhelps!