There is any easy and safe way, it's called don't worry about it tipping because it won't. It would be practically impossible for it to tip with 6 people in the cab over if you could even get them in there.
Supports under the camper don't address the OP's "supposed" problem. The pivot point would still be the same: the front edge of the camper where the jacks are.
Think of it this way. When on the jacks or on the truck there is no support any further forward. How many trucks do you see with dented cabs because the camper tipped forward in the back of the truck? I'd bet none. If it won't tip on the truck it won't tip on the jacks.
We use ours a lot just sitting on the jacks. Lower it down as far as you can and it will be very stable.
