Spare a thought for these two poor sods over-nighting in a Sentinel DG6 'sleeper' steam wagon back in 1928. No mattresses, no curtains and no windows either. This really would have been just one very small step away from sleeping rough.
But what they did get was a huge amount of heat from that massive boiler. I'm sure it was welcome in the winter - but not particularly pleasant in the summer months.
What¹s the worst truck you've ever slept in?