how hard would it be to put a M62 onto a M45 kit?

BTW i have done a FMIC on a mondeo turbo-diesel (non-aircon so theres plenty of room) - for now i have put on a small-ish intercooler low down at the front. but i have just bought a saab 9000 big intercooler and tried it in there and it fits a treat and is very easy to mount. hopefully this weekend i will get it in place and connected up.