I did this a few months ago and tried to avoid the main routes as far as possible.
Your route actually starts at Elandsbaai where you take the road next to the railway line'
Then Doringbaai, Lutzville, Groenrivier, Hondeklipbaai, Kleinsee.
At Alexanderbaai you can take the road to Luderitz via the 'Spergebied' if you do not enter Oranjemund but even the border officials aren't very sure of this so try to get a permit otherwise you will have to go via Sendelingdrif which also isn't bad as far as borders go.
From here you go to Aus, Helmeringshausen, Sossusvlei, Sesriem, Walvisbaai, Swakopmund.
I towed my 6ft Venter with no problems. There are however a few places with loose sand at Groenrivier but it poses no problem with slightly lowered tyre pressures. (I did the whole trip @ 1.8 bar)
2006 Patrol 4.8 GRX Tiptronic Y61/GU(4)
ARB Bullbar, TJM 2" Suspension, Snorkel, 285/70/17 BFG KO2's, 40L Engel, Nuvi 1410, TPMS, SatNav
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