first off it's the screen. that's if the wiring is the same.
then comes the headunit, does that have the right menu buttons for controlling it? if not that'll need swapping too.
then a session on the tech 2 to turn it all on.
whether or not you'll need any of the associated sensors to go with all the functions is anyones guess as you know what vauxhall are like.
tbh a good search over on vectra-c.com might turn up some information