If you fit a pro alloy or pace etc then if pipes correct size all you need are 2 bolts and rubber mountings same as on rad, all existing hoses fit fine, although if you need a dump valve then it requires a new hose with take off, if you mean a genuine cooler then you need mountings as above, and either some hoses designed to fit from 3" cooler to 2.5" throttle body and to T3 turbo, I think roose motorsport do them, or as I have done and use std 500 hoses, had a silicon hose sleeve made up fit to turbo from roose motorsport and had my throttle body sleeved up to 3" with alloy sleeve and bored out into a smooth cone inside, then I also needed the alternator drop bracket so that the 500 hose on turbo side missed the alternator, so as can be seen there are a number of ways to tackle it, but I have had a pace one and changed to a genuine one as it fits alot better, and have also used RS500 air inlet to direct the cool air from behind the grill into the airbox.
hope this helps
Darren