Welcome Shazza n don we went up there in August 19 with an 05 patrol Ute towing a black series dominator camper with no real issues , we also never did the lets see if we can drown the Ute and camper crossings though however
I would strongly recommend that you have a sound knowledge of the mechanics of both you tow vehicle and van as there were some with issues mostly small though that we came across , one was an off road caravan with water pump issues because of very poorly mounted and wired and located pump but a relatively easy fix if you know what you are doing .
Another van where a bloke had fitted new springs but neglected to do up the U bolts tight enough and lost them both , probably distracted while doing it and never did a final check .
Saw a few standard vans up there too don't know how they got through some of the creek crossings they were on their way up so I dont know how they got on but I sure wouldnt recommend a standard clearance van for the trip.
I took spare belts and spare wheel bearings for the camper only needed to adjust them once on our return and two spare fuel filters only used one took two spare air cleaner elements didnt even use one , I did fit a snorkel before we left though but the main reason was I didnt follow in other peoples dust , not that silly .
Also drive at a safe sensible speed make sure you have plenty of time , dont rush , let the maniacs go past you , and theres a few of them up there happy to pass you even if the cant see up the road in front of your dust , did I mention dont rush take your time , this will potentially save you a lot of heart ache and money .
Sealed roads yes theres a reasonable amount of it but so there is of corrugated dirt roads but there not as bad a some would have you believe, mind you Im from the country in north west Vic I am used to rough dirt roads, drive to the conditions and your skill level and you should be ok .
Lots of people will tell you to lower the tire pressure well each to their own I did the entire trip with 42 psi in both the Ute and camper , oh and never had a flat there either, point here driver skill know where your Tyers are under you and you can dodge any rocks that might be on the road here n there .
Seen A few highluxs With cv joint boot issues from stones and sticks that went off on the side trips , also a couple of drowned Utes one from WA long way to have your camper towed ! Also tol that the V8 land cruisers dont like getting wet apparently the starter will die about 21 days after the swim .

In a nut shell preparation is your best defence against preventable issues before you leave , have your rig serviced just prior to leaving .
Drive sensibly at your skill level , dont rush , have a good basic at least knowledge of your rig, carry a few spares as indicated above,
There is fuel available at reasonable distances yes its dearer than on the coast get over it its a whole lot better than being stranded and walking .
Our Ute caries 170 L but we still toped up at most fuel stops just to be sure as the Irish day .
We found it a good trip , bucket list thing probably wont do it again though .

Proper Preparation Prevents Piss Poor Performance

Drive sensibly , take your time dont get pressured by some one following you to drive faster , pull over and make them pass you if there pissing you off driving so close , above all enjoy the trip is quite doable with a well prepared and appropriate rig .

Do stay a night at Bramwell station and book the meal and show it was fantastic .

Enjoy

Woody