Some bright colleagues put together a script that pops up with a dialog in the UI to allow you to change the elevation of your viewport using this script (included in post). Give it a try, it only takes a moment. The script will allow you to change your viewport elevation by any numeric value you specify. The elevation uses the units of measurement specified in your model, so if you are using meters to report elevation, then your changes to viewport elevation will adjust in meters as well.
Here's how you do it: