So you haven't been able to rescale the drawing so that it is full size in model space?
What scale did you draw it at to begin with?
Remember that you are not drawing in CAD as you would on a drafting board. You do not have to "draw to scale". You draw everything full size whether it is a paper clip or the QE2. After drawing your objects in model space then you switch to a paper space layout and utilize viewports to see what you drew back in model space. Think of a viewport like a window. It is these viewports that a scale gets assigned to. Text and dimensions can go in either model space or in your layout. Each requires a slightly different method.