If you van is a few years old then the countless number of times people have hauled themselves into the van using the door will likely have caused it to drop. A good symptom something is wrong is if your doors bounce open when you close them occasionally. When the door is nicely aligned you have an equal gap around the door when it is closed, the door latch pin will be central and it closes with ease.
There are a few good guides on Sprinter Source (as usual), the top two chrome bolts are for the wing mirror, the third hidden wing mirror bolt is behind the black circular black plug.
That leaves four bolts two at the top, and two at the bottom. I undid all four, jacked up the door and set the door to the middle of the door frame, I then jacket the corner of the door up and set the angle, and thus set the door pin to the right height and tightened up the bottom two bolts. Time taken is about 5 mins per door. I highly recommend unbolting the mirrors to set their height to ensure that they fold correctly and don’t pinch on the mirror join.
Next up was to treat and paint our wheel rims. The steel rims were gnarly and rusty, they needed to be sanded down with a grinder and wire wheel, sanded some more, treated with rust converter and then painted with rust protecting paint. Painted black because I didn’t have any silver… Central hubs were also treated in a similar way, then the wheel studs were greased up and the wheel nuts reapplied. Don’t forge that there are small cone washers behind each wheel nut and to jack on the correct point. For reference our wheel rims are marked 5 1/2 Jx15H2 HMA 115.