With the headliner, it's just a case of making sure you've removed all the ancillary parts before pulling on it. While its off, I'll probably put in a layer of sound mat aswell to kill off some of the road noise. The DC5 comes with no sound proofing at all to keep the weight down on the car, but I'm going to be putting a little into it just to take away some of the noise from the exhaust and mani etc.