As much as I enjoy filling my inbox with messages Ima start responding here.   

  Steve Thomas is right.  DK monitors were 19".  The reason I thought they were a 20" inch is because they were a 19" Sayno EZ-20.  And that is what I remembered the EZ-20.  I'm not sure what direction you are going in but by your trailer I assume you are going with an original cab and not a Donkey Kong run by a computer.  I don't know how rare they are but I would keep looking around to see if you can find a 19" monitor.  It took me a while to find my Nintendo coin door but I was glad I didn't put anything else in its place.  Haste makes waste.   

Good luck. I'll be watching this build.