Bongo Fury

Both the Horn and the steering wheel push switch actually work but not together! Mechanic says he needs a wiring diagram. Can anyone help? It might be on page 78 of some publication but I don't have access to it. Not sure how to proceed. Any ideas?

Wiring diagram is available, on CD, from the Club Shop - it is also being made into a free download, but not sure if it's been done yet. Email Ian to find out.