I followed the guide on here, took probably 4 hours as it's the first time I'd done it and I wrapped the manifold. I dropped the subframe pretty much down to the floor whilst the car was on axle stands, makes it a LOT easier; just watch for any cables/pipes (e.g. brakes/PAS) being stressed when the subframe drops. The guide on here was written very well and the photos show you exactly what you need to remove. Make sure you get a fitting kit and a new exhaust manifold gasket. Also be aware that the 182 manifold is a lot 'longer' than the 172 one, therefore you'll need a 182 -> 172 link pipe/decat (or sports cat) to link it to your 172 system. Don't expect the 182 manifold to link straight to your 172 center section!