Ok well firstly for the bootlid, there is no trim panel for the underside, so that's one thing you don't have to worry about at least
Do you want pre-facelift or post-facelift nostrils? (either will fit, just a case of preference really).
Did the car originally have air con? I.em has it got an air con switch on the control panel and does it still have the matrix pipes poking into the engine bay? Also, does the car have ABS or not? (believe it or not, this will affect what air con pipes you need to get up).
You should be able to pick up the parts you're looking for relatively cheap. I wouldn't bank on finding a good second hand air con condensor though (that's the big matrix that sits in front of the rad). You may well need to go new for that...