Hi guys, ive just got a replacement swinging arm for my 2004 blade ( the old one had one of the padock bobbins snap off complete with the welded threaded bit ) So Im just wondering how a bit a job it is to change this like for like , anything to look out for ? hints and tips most welcome - ps I have no manual atm - should I get 1 before I start ? many thanks in advance for any input at all