I'm building a model that's very small, about a square millimeter, that I intend to have 3d printed. I've figured out the model at normal blender dimensions, with the units set to "None", and then I just set my units to "Metric" and scaled the thing down considerably.
Although I could use this model, I might want to make further changes, but since it's so small, it's difficult to work with since the viewport panning is messed up so closely zoomed.
How do I change the scale of my viewport from "meters" to something smaller, like "milimeters"? I've googled around and only find unrelated information.
Here's a screenshot to illustrate my problem.
Notice how in the top left corner of the viewport it says "User Persp" with "Meters" under it. I suspect that's what has to change.