Pablo,
Welcome to iRV2, we're really glad to have you here as a new member and are looking forward to reading your posts about your RVing experiences and adventures n your new fifth wheel. You'll find a great bunch of folks on this site who are
very knowledgeable of RVing, the rigs we use, and the places we go in them.
As you'll see, they're eager to help and share their knowledge and experiences with others.
Take a real hard look at the towing weight limits for your F-150. You don't say whether it's a crew cab or what axle ratio it has, those factors will make a difference. The Trailer Life 2006 Towing Guide indicates an F150 SuperCrew SWB 4x4 with the 5.4l and a 3.73 axle can tow up to 9200#. With the 3.55 axle it's 8200#.
Also, the 6300# UVW for the trailer is most likely on the low side, I wouldn't be surprised if it weighed a few hundred pounds more. Load it up with your stuff, food, clothes, water, propane, etc. and it gets heavier.
Find out what the GCWR is for your truck and then load it up with all your usual stuff, including the passengers it'll be hauling while towing. Take it to a scale and weigh it, subtract that weight from the GCWR and the answer you get is how much you should tow.
Also, subtract that weight from the Ford's GVWR and that's how much pin weight you can handle. You may be surprised at how little carrying capacity you have with the Ford, the only way to find out is to do the math.
Most folks towing fivers with 1/2 tons are disappointed in the performance.
Again, welcome to iRV2, we're glad you joined. :wave