Dual Boxing with different resolutions

My sister game me her old PC monitor to go along side my wide screen one. Is there anyway I can have 2 instances of the game with different option settings? I'd like to be able to have one on each monitor.

Using the old launcher, yes. You'd add a command like "-screen 16580 1050" (for example) to the shortcut, but I am unsure about how to do it with the new launcher. I know we can add the extra commands inside the new launcher but as for how to add 2 separate customizations, I haven't yet tried.

Edit:
If you know about the registry (and are comfortable changing it), you might be able create a *.reg file for each resolution, and then load one before opening each instance of the launcher. It's an extra step, but the only other thing I can think of at the moment.

Just an update incase anyone else wants to do this, with the server list merge you can install 2 instances of the game and run them with separate settings.