Multi 4K screens

i have a project that is being rendered across three 4K displays at a resolution of around 11000x2160. I am having to figure out what hardware I need to run this and I am currently weighing up a single beefy GPU with three display port adapters or three GPUs to drive each display. My preference is for the three GPUs to share the load and then use the NVidia control panel to extend the desktop as one huge display. I am after any advise going really to help guide time to get this right as I am sure other people have done this before?