Access along the Mount Davies Rd

Mt Davies road no longer exists. There is nothing of southern end left and you cant get permits to even try.
Access from Surveyors General to Stuart Highway is also very difficult to impossible to get a permit for

Ray, you will need permits for the Blackstone Road. Not easy to get but not impossible. You'll be required to show cause as to why you need to use that particular road instead of the Great central and accessing Surveyour Generals Corner via the northern section of the Mt Davies Road.

Mount Davies Road south down to the Anne Beadell is another matter entirely. They will not issue permits for the road and you'd be hard pressed to attempt it anyway. It is not maintained and unlike many other Beadell roads, it has seen no traffic and is largely overgrown and impossible to follow.

Permits for the APY lands on the SA side of the border are difficult to get particularly of you want to deviate from the main roads as you do. .

From the Anne Beadell, you'll find out pretty quickly how tough things are going to be. Extremely over grown and the dune crossings in particular are often totally overgrown.

I went overland from Maralinga to the Everard Ranges in 2016 (on a quad bike) and it is pretty unforgiving country. The country further west that the Mount Davies traverses is even tougher in my considered opinion and those that have attempted it.

Hope that assists.

Regards and safe travels.