Hey 1/2. In my GMC van, there is 74-76" across in the back once you remove the lashing boards, so enough width to put in a standard size twin or double bed crosswise. Your SnowBeast looks wider across. Some guys do sleep at a slight angle in their van beds. People with vans often buy foam mattresses, and these can be trimmed to fit using a carving knife. I have this one. I also sleep on my side.
- https://www.amazon.com/gp/product/B006L9QN4G
- https://www.amazon.com/gp/product/B006L9QN4G