Any way I could use https://thepihut.com/products/adafr...button-with-blue-led-ring-16mm-blue-momentary to use instead of the existing power button? I don't mind if it doesn't shutdown the computer saftely, I just need it to turn it on.
Yes you can, you have to connect it to the header for external buttons/LEDs AKA front panel pins. All the details are in the user manual (PDF) page 30, you can download it from here https://www.udoo.org/docs-x86/Hardware_Reference/Resources.html
I use one of these: https://www.amazon.co.uk/gp/product/B00HG7HO22/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 Connects to the header pins on the UDOO and works fine.
