I use a small floor jack to lift. Then once the van is on 4 UniJacks, I lift it up to where I am comfortable crawling under.
You can use ramps, jack stands, or whatever you want. Personal preference is not to use the OEM emergency scissor jack, ever, on any vehicle. There is even an inflatable balloon jack that is perfect for lifting a low profile car to a comfortable height for service.
Just don't buy a used jack at 007's garage sale. He only sold it because it doesn't work.
And when he gets a lift, all the Left Coast members are going over to his place.