Hiya
There will somewhere be a Mercedes body building guide saying what you can and can't cut. I seem to remember if you want to fit a camper roof to a Sprinter like a James Cook you can't cut off the whole roof for instance. I imagine cutting off the whole body would need you to add the strength back in which will be the same weight and more plus the box.
If you were to buy a ladder chassis there's nothing stopping you mounting all fluids batteries etc along/between/under chassis legs? A big empty box on top won't weigh much.
|