So for our second jaunt up to the NT/SA border, things went a lot more smoothly. It's still not something I particularly enjoy - going hours without phone service on a sparsely traveled highway - but at least nothing went wrong this time.
The last time we were up this way, all hell broke loose under the bonnet of the Transit and we bolted back for civilization, eventually learning that it was a diesel injector pump that took the injectors with it.
This time we're in our own van, thus far things are going a lot more smoothly and we'll make a lot more money when it's over.
I have a few minor mechanical concerns with the van that we will fix up in time, but at least it's not "hunting" on the highway and threatening to die at any moment like the Transit.
Duncan is really enjoying the trip too, his spats of not wanting to be in the seat are getting fewer, and we didn't even bring the TV we bought for such occasions.