Stretching Keynote over multiple monitors

I have looked and looked and whilst I can find many suggestions for my issue I cannot find a solution, not one that seems to work (in software). I have two projectors (or monitors) connected to my Macbook. Both same resolution, etc. I want to have a Keynote that stretches over both displays with the notes on my laptop. So my thought was to disable spaces, create a presentation that is the width of the two monitors combined and hope it would stretch over. Nope. So with my understanding the only way to do this is to trick the OS into thinking the two projectors/monitors are actually one. So there is then the Matrox DualHead2Go. However that is expensive and for the amount I will use it I couldn't justify the cost. Thus I was wondering, and I have looked, is there a Virtual Monitor Driver? Something that will do the same just in software? I did find two on GitHub but over 4 years old and will not work on anything > Mac OS 10.9. Any suggestions?