Aside from finding a place to mount the mobo and ioboard , the only issue i could see is the touchscreen glass not working with the force touchscreen controller if the XL has a ELO touchscreen. If it has the 3M microtouch SMT-3 then you can just swap the black force controller out and your good to go.
You will probably need to use the force power supply aswell and depending how the switch in the back is wired you might have to splice something like a surge protector in to the hot, nuetral, and ground so everthing turns on when you flip the switch.