I think the whatsitmathingajig on the swingarm is a token effort at the chain guard required (to my knowledge) to get a bike road registered in Australia.
KAY DEE EXER, I notice your friend kept the American theme throughout the Datto by keeping the drum brakes on the rear ;) Next time you're the designated driver on a cruise up to Newcastle give me a call so I can check it out! We've got an old 260Z in the graveyard at home (...shame it's a 2+2) and I would love to restore a 240 one day - rubbery-look matt black finish, of course. You don't have a friend with a DeTomaso Pantera too, do you?