Thanks fellas, for your input.
I think this person (Dave Dixon) from the US, now has enough info.
Below is an email from him :
" Hi Gav,
Thnk you for helping, That is good to know on the fenders. I like the look of them, they grow on you.
I have built a ton of RM500's and I am very excited to build this bike. It is special.
I have obtain a lot of pictures from Rosco and others in Australia. You guys down there are great, I am very impressed with the entire group.
Because of all the help from you guys, I have enough pictures and details on this bike and the project is now a go. (After I am done with a 1984 RM500 I am doing now.)
Thank You
Dave Dixon "