ok, finding out 421 systems for a K series are a bit thin on the ground used,so I have sold my soul and purchased new from Caterham . I will be fitting it over the coming month once I get the car MOT'd Any tips on cutting the hole in the body (tools and technics used?) .Also considering giving the system a polished finish,again tips welcome.Do I have to change anything under the bonnet on my 2005 s3 imp chassis? Alternator and starter ok?,would you used wadding to keep the heat down?