Any additions will not increase your towing limits. They may make it tow the load easier, The Scorpion has a gross weight of 6800lbs (3900lbs trailer - 2900lbs payload including propane, water and supplies)
I don't know what the tongue weight limit of your dodge may be. I do know the F150 is rated for 500lbs and 990lbs with an equalizer hitch. Check with your dealer on your towing limits before getting a hauler.

 

I don't think it's really an issue of being able to pull the rig that matters. You have to consider things like braking, handling, frame strength, and suspension capabilities. Ever heard the saying "the tail wagging the dog"? This would apply.

You are VERY underpowered with that powerplant too.

Would you buy a Grizzly for MX racing? Would you buy a YFZ to work on the farm? Why not buy a truck that's meant to tow heavy loads?

Buck

 

If you stayed with a Very Very small toy hauler you would probobly be ok. The Scorpion is probobly as big as you would want behind your truck. There are a few other manufacturers that make modeles that have racks on the front of pop up campers that would be much more the size for your truck.they have room for 1 or 2 machines on them. I cant remember what they are called but I have seen them before. I think they are made by Jaco. One other model I have been thinking abought is the Tavel Star. I cant remember who makes it but it is basicaly a 18 foot camper on a 26 foot frame. The front 8 feet are a open rack to haul 2 machines. Do a search for these.