There seemed to be a lack of detailed mapping of the circuit which would potentially be of use to supports crews and others. I've plotted the route and here are a series of maps with the route in blue which I hope will be helpful. If there are any errors in there I apologise, but I'll not be making any changes :-)

Start to Prees Island - Segment 1

Start to Prees Island - Segment 2

Prees Circuit - Segment 1

Prees Circuit - Segment 2

Prees Circuit - Segment 3

Quina Brook Circuit

Return Route - Segment 1

Return Route - Segment 2

Finish Circuit