[HELP] Using thunderbolt monitor but with discrete graphics support?

Hey.
I have a GA-Z270X-UD5 with on-board graphics and thunderbolt 3 which is currently running my Thunderbolt Display. I also have a gtx1060 installed running two other monitors. The on-board graphics is the only thing that I can get to power the thundebolt dislpay though. Is there any way to still use the thunderbolt port for video yet disable the iGPU/on-board graphics such that my 1060 runs everything? I know that the display HAS to be plugged into thunderbolt for starters.