Okay, so, Unity is kind of a pain, but I did manage (with lots of help and the use of a pretty good tutorial here http://www.41post.com/4162/programming/unity-raycast-reflection) manage to put together something that I want.
There are still some bugs. For one thing, the way to select the mirrors is stupid right now, but that’s fixable. You have to click and remain hovering over them with the mouse, then spin them using the left and right keys. More concerning is the fact that when I have two beams hitting one mirror, the first reflection beam is replaced with the new reflection. It shouldn’t do this. I guess it should display both? I don’t know, that might just be annoying. I’ll think about it.