You can create some sketched lines with equal length relations and use those to help get the spacing by eyeballing, and then delete or hide the lines. After that, if you want to move them make sure you Ctrl+select them all so they move together. Other than that I don't know of a way.
I was hoping there was a way to do this with some sort of control other than just by eye. I tried to sketch lines between views then change the length of the line with the line properties dialog. That didn't work either, which isn't surprising given that you can't use a dimension to drive view location. I also looked for a move view command where you could move a view a specified amount. If that ability existed you could measure between views, then move the required amount. Doesn't seem that a function for moving views exists either (other than drag).
What a drag......