drawing files do not currently support equations.
simplest work around I can think of right now would be to have 2 sheet formats, and switch to the one with "see note 3" when you need the space.
I am afraid that is the case. My alternative is to create separate layers on the drawing format like....
FINISH - Drawing
FINISH - Assembly/Part
.. for each property strings in question to reside on and then use the "Layer Properties" dialog to turn them on and off alternately.
But I'm just hoping for better.
I would like to recomend a Property Tab Builder to you. You can search for some tutorials. It's powerful yet underestimated tool.
I can assist you with some tips tommorow as i'm busy right now.