'Ello, my friend. Well, I've spent an interesting little while searching, and didn't come up with much. I learned via Google that a scuttle: a.) has a frame and b.) sits on the chassis. Woo. I did find this--perhaps you can make more sense of it than I could:
http://www.daxrush.co.uk/part5.htm

Might try diy parts shopping (diy so as to help ensure that you're on to a UK site); you might get lucky and get a picture.