Take a look here:
http://www.gastric.com/toys/ducatibip2mono.htm This fella basically wanted to be able to do the conversion quick and easy by having two complete seats setup to just swap and go, not forgetting the pillion pegs of course.
I am doing the same thing myself. Some bits new and some bits from Ebay. If you want part numbers and diagrams go to the technical bit of Ducati.Com and download the spare parts catalogue.
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