Hi Simon
check out: http://www.flickr.com/photos/l_atalante/sets/72157608585108667/
For photos of getting one apart and all of the components. The one I got apart was my spare, I had to cut the one on the boat into bits to get it off. The spare came on a chunk of bulkhead attached so whoever I inherited it from had a few problems too!! I ended up recycling some parts and having new ones made.
Trevor has the drawings.
Murray A87