I think there's a bigger issue at hand if your having to get underneath the truck while your rotating tires.
Seriously though I get the safety aspect everyone's singing about but really guys. The front would be secure on jack stands, presumably the OP is on level ground.. I hope... I doubt it would be that much of an issue to just have the rear elevated enough to get the tires off..
simple process if you only have two jack stands.. jack up the front or rear secure that end of the vehicle on stands. take that end of the vehicles tires off. move to the other end of the vehicle. Brake loose the lug nuts, Jack that end of the vehicle up. When you take a tire off, put one of the rotated tires back on, move to the other side. Complete that end of the vehicle. Put that end of the vehicle back on the ground.. move back to the other end of the vehicle, put the remaining tires back on in the appropriate position..
Don't get under the vehicle if you feel the vehicle is not stable in anyway..
You can have ten jack stands.. its still dangerous to get under a vehicle.. Take risks, get it done, move on, live life..
Oh by the way someone may hit you if you drive your vehicle on public roads.. best to keep it in the driveway if you want to avoid a wreck.