I am working on similar set up.
I setup using cheap video card I got off ebay and I worked OK.
I am thinking about GPS on one monitor all the time, and whatever frontend
software on second. Correct me if I'm wrong, since none of the frontend software support dual monitor (as of now), the GPS need to be not embedded in frontend software.
I got bigger issue to work put right now, but it should be nice once I get this setup in my car.