This Sunday is a bit short notice for most people Shaun.
As for Route.....why not start at the Museum (meet point) then head up Parks Way to Coppins Crossing turn off?
Head down there and then make our way onto Uriarra Road (right hand turn). This will lead us (the more exciting way) to the Cotter BBQ area where we could stop and have lunch/food/break.
Those who want to depart at this point can take the short route home while those who are game can continue onto Tharwa and even further beyond (the roads after Tharwa are just awesome).
You'd be looking at about an hours worth of driving (not including breaks and stops).
It'd also be great if peeps could get their hands on CB's for such an event.
EDIT: Hell, if time permits we could even pull into Tidbinbilla Reserve or the Deep Space Tracking Station and grab some awesome pictures. If you wanted to do this you'd need to start around 1330 - 1430 to leave enough time before dusk (those pesky roos).