There are very few campers that will properly fit both a long bed and a short bed truck. If you use a long bed camper on the short bed it will hand way off the back and the tie down brackets will likely be in the wrong position. Center of gravity also will probably be farther back than you'd like. If you use a short bed camper on a long bed you have to build some kind of frame in the front to keep it back from the front of the bed. This is to prevent the "wings" from contacting the tail lights. This does give you storage in the front of the bed but it looks funny.
You will run out of payload on that truck very fast. You would need a very small light weight TC to be able to haul it, tow the boat, plus haul all your family and stuff. I would seriously consider upgrading to a long bed dually.
I don't know of any camper that would hang down so far you couldn't use the hitch. I've never seen one and it would be rather foolish of the manufacturer to make one that way. It would defeat one of the big reasons to own a TC.
You will need a hitch extension of some kind. I used a 48" Curt to tow my 20' boat on a tandem axle trailer, total weight about 4,500 pounds. It worked okay. When I started using my dually I installed a Super Hitch with a 48" Super Truss. It is much stiffer and rated for a bit more weight.
