What trailer do you have - or are you still shopping? If the trailer already has an extended pin box (many do), you may not need anything. You also need to estimate where the hitch will be in the truck bed and measure the distance to the back of the cab. Usually the hitch pin is located about 6 inches forward of the rear axle, but on a short bed you can 'cheat" a bit and set it a couple inches further back to get some additional clearance. This has a small negative effect on maneuverability (you have to turn the steering a bit more to get a backing turn started) but may be worth it. You can estimate the potential for hitting the cab by measuring from the trailer's pin to the front corner of the trailer and comparing that to the distance from the hitch point to the corner of the cab. But if you don't want to do the research, you can always fix it with money (i.e. buy the sliding hitch). Manual release sliding hitches are less expensive than the Super Glide, but you have to get out and pull the release lever, either every time you back up (to be fail safe) or only when needed (back to the awareness issue again).
But I towed a Wilderness fifth wheel around for three years using two different short bed trucks (a GMC Sonoma and a Dakota) and never once came close to a cab strike. We went to all sorts of forest service campgrounds and places where we did a lot of maneuvering to get on the site. And that's back when I was new to fifth wheels too. It is not a given that you will have a problem with a short bed truck.