Is there any way to safely and effectively get fleas out of a vehicle within 16 hours?

See this question for background. The car is a minivan, and it has cloth seats and the usual carpet on the floor. All the online advice I’m looking up, and the vets whose offices I’m calling, say that you need at least 24 hours to completely eradicate them. Does anyone have experience doing this? Can we get it done faster? Cost is no issue.