Macpro 1,1 Windows 10 auto boot up question

Hey guys, I recently installed windows 10 64 bit to my mac pro 1,1. As some may know this is bit tricky compared with newer machines due to the 32 efi. Anyway I got win 10 running on a separate drive but every boot up I need to press the option key to select the drive and boot. Is there a way I can make this automatic? I have tried the osx startup utility but this did not work. Any ideas welcome thanks!

Author: @FlightOfFate