Had to rummage through my cobwebbed memories and tease apart what each element in this system does.
DialogueHolder: Holds dialogue for each game object, simple text holder. Assigned to each dialogue trigger zone. If the player is in the zone and they press a button, the DialogueManager is populated with the lines here and notified to display them.
DialogueManager: In direct control of the text box. Sets box active, displays the populated lines one at a time, and tells the player to stay put while the box is active.
Ran into a bit of a snag with this setup. The holder has to fire off the first text display for this code to work. Now the text scrolls as expected!
-Streamline dialogue and add response choices
-Add simple background