Hello, the internal set is fitted by removing the control knobs, the front one just pulls off, the large one has a circlip, then you need to undo the large headnut 55mm hex, at this point you should have turned the water off, or you will get very wet. Once the head nut is undone the internal set can be removed, the body cleaned out and the new internal set installed, if you need any other parts I suggest www.showerspares.com
gary, November 2012
