since you need something to send the gcode to grbl only solution I could think of would be to use a pi and a usb thumb drive to send to the uno. then you should be able to use displays and setup things the way you want and not have a monitor installed to operate if setup correctly I was pondering doing something like that one day but my machine doesn’t take a break long enough for me to tinker with it more. so I am building another with ramps. GRBL has its limitation its probably not impossible but having something sending the code vs ramps that can read it and output the code. I have had no issues with GRBL and will probably stick with it as much as possible ramps will just be for my laser setup.