After replacing the points (which were the orignal Delco-Remy part, and seemed to be conductive at all parts except the contacts), emptying and rinsing the fuel tank and unblocking the fuel line, and priming the pump and a big shot of ether into the carb, he runs.
We then flushed the radiator, though it will still need to be done 'properly' and maybe a new thermostat would be a good idea. We're going to have to do an oil change and replace the filter too, but we're going to need quite a bit of oil (~8 litres) to do that properly.
Runs very well actually, one cylinder might not be up to par, but good enought to get about with. This means that it will be reasonably easy to get the Yellow Truck on the road.
The next step will be to overhaul the brakes, as they don't work at all. Most likely the master cylinder will need refurbishing and the slave cylinders will need replacing, fresh fluid too.
We also need to look at the electrics, the horn gets stuck on and none of the lights work.