There's a solution!
Let me back up a bit. I'm building this game in Unity, and it's a mobile game.
Because of that you have to deal with various screen sizes. Having been developing web applications for the past dozen or so years, the hell that can be writing CSS/HTML so that it "responds" to a viewport that is smaller than your typical desktop/laptop viewport (i.e. phone).
Yeah, anyone reading this knows all about this problem. But, I'm new here (the Unity world) and screwing with anchors was only making things worse.
It's as easy as creating a new C# script in your Unity project, then drag that script (I named it
GUISizer.cs) on to your scene's camera object.
That way your entire scene can easily respond to different screen sizes and resolutions. It's pretty basic really and saved me a massive amount of work and wonder.