Reconfigure Thunderbolt DisplayPort Monitor Ordering I have 2x Dell U2412M monitors connected via Thunderbolt/Mini-DisplayPort. Even when I swap the ports connecting to the Mac, the monitors keep their #1 and #2 designations.

My physical monitor plan: Macbook Pro, Dell #1, Dell #2.

Software ordering in OS X: Macbook Pro, Dell #2, Dell #1.

Is there a way to get OS X to change the order of recognition for these monitors so that I don't have to physically swap their positions on my desk?

Edit: More specifically, I want the order of the IDs to be swapped. They get registered with the system as #1 and #2, and I want that to be swapped because it has an impact on directing windows to monitors, particularly with VirtualBox. I don't merely want to "arrange them".
System Prefs > Displays > Arrangement.

Drag one monitor over the other to the opposite side, then move the Menu bar to whichever monitor you prefer.

The actual screen is given a large red outline as well as the representation in the control panel as you drag, so you're certain which one is which.

BTW, that tenacious holding onto which display is which is a whole lot better than it used to be, where it would randomly decide 2 identical screens were the opposite way round on occasions - back in 10.6 &amp; before.