The one I did was the Canadian/American model and was fairly easy to remove the digitizer alone If Samsung and apple both start doing sealed units these units are going to be worthless after a screen break. The iPad air 2 for me to repair total all in out to the customer is $400 CAD. Tough to justify a repair that's well over half the cost of the device at any age.
Hi , None of these will work, with the new UEFI locked out bios, and secure boot enabled, you need to access the bios (F10 on most HP Systems) go to boot settings, disable Secure boot and enable Legacy mode, you should then be able to reboot, hit F11 or F9 to get to boot device selection and then install your new OS.
My first step would be to tear down and check all connections/ribbons etc. unplug and reseat all connections, if there are ribbons involved ensure all are all the way in to the sockets (up to the white line), and re-assemble and test. Something else that has happenned in the past, is one of the cables were 'pinched' between chassis parts on re-assembly, causing a weak connection to the component, so make sure all cabling is in it's proper pathway. Xpider