So ... when I use a floor jack on the lift point, where do the jack stand(s) go.
IMHO, if you’re lifting a vehicle for a job, you should be using the manufacturers listed tools and their documented lift points, using their documented procedures.
If you’re lifting your personal vehicle, then I’m not going to tell you how should lift your car. I can only tell you how I do it, and what I have read from others.
I use a Hein Werner 93652 jack and US Jack 6 ton jackstands. Of note, the saddle on the jackstands is flat rather than V or U shaped seen on most stands (see:
https://www.usjack.com/products/garage-jack-stands)
I think the tools you use should influence how you decide to do things,
For the front I have lifted from the round bar jackpoint as well as the adjacent vertical tow hook area, and I’ve placed my jackstands on the body-frame rail just behind the transmission crossmember similar to where the shop lift would go. For the rear, I lift from the shock mounts and put my jackstands on the body-frame rail just in front of the front leaf spring mount. I have used the these points numerous times for rotating tires, changing brakes, flushing brake fluid without problems.
I have not tried these jackpoints, but I have read/seen reports from others on the internet that have successfully used the front lower control arm, front subframe, front subframe mount, rear differential, and rear axle where the U bolts are located as alternative lift points. Of the front points, if I were not able to use my preferred lift points, I would try the front subframe mount. In the rear, I would probably not consider using the rear differential if the van was heavily loaded, or converted such as a campervan etc. as I think the weight limit on that rear axle is somewhere around 2.5T. (obviously also be careful not to screw up the rear differential cover). I‘d be extra careful of the outer portions of the rear axle, where the U bolts are located - mostly because the ABS sensor wiring and the parking brake wire are in the area that could be pinched between the jack saddle and the axle.
On the other hand, I’ve seen a handful of internet reports that have lifted from the pinch welds, resulting in bent or crushed the pinch welds. IMHO, Im not going to lift the transit from a pinch weld.