I ended up attaching my day packs using toe clip straps. The benefit of these is that they are strong and that I havent had to mod my packs. I then cross lashed my extra gear. Unsurprisingly, this is the easiest way to attach the stuff and is stable.
With the last few weeks before the tour, its now time to square away a project at work, get a sleeping mat (I want a self inflatable mat), and contemplate a returm flight. The other 2 will be booking their flights to George shortly so we are all on track.