What's the easiest way to get this done? I've been having trouble finding a solution that doesn't require an entire UI rework.
I would start by hiding elements in ConsoleUIContainer, FullscreenUpperContainer, etc that you do not need (<Visible val="false"/>).
And then you move the InfoPanel around.
You can use the ingame UI editor to figure out which elements are remaining visible on screen (right click the area on screen -> chose frame in dropdown) and check their path, so you can hide everything one by one.
Please note that there might be a few unusual frames that do not respond to <Visible val="false"/>. If that is the case, I recommend moving them off-screen via editing their anchor offsets.
Also, you might want to edit GameUI's properties to remove the black bars. But please note that this also edits where the camera centers in case your map is a melee map. Zerg players do not like that when they do injects in all bases and use that hotkey that cycles through all bases.