How to scale dimensions proportionally to a specific size? I modeled a man and would like to scale him down to be exactly 6' tall (Z dimension), however I cannot find a way to do that. I know I can go to front ortho view and and use the normal scale S  key to scale it, however that requires some pretty specific fine tuning in order to get it to the right dimensions.

I'd like to be able to essentially type "6" into the Z dimension (don't worry I have it setup in imperial) and have it scale the X and Y dimensions proportionally.
As far as I know it can't easily be done on a single atomic operation unfortunately, but I generally use the following workflow.

To scale uniformly with precise absolute dimensions, in the Properties Area of the 3D View just type in the exact absolute dimension you require on the single desired axis.

Now check the resulting scaling on that axis, Blender will have calculated the appropriate factor for that vector. You can now copy-paste the value with Ctrl+C, Ctrl+V to the other axis so they all remain uniform.

Apply the scale afterwards if you desire with Ctrl+A > Scale while in Object Mode.