Cody, a Bradley heating element has a threaded metal stud sticking out of either end. The power leads coming through the back wall of the smoker, behind the ceramic heating element holders, have a loop fitting on the end. The loop goes over the stud and is held in place with a nut.
To extend the wiring, you take a 2 inch or so piece of high temp wire (from an appliance parts store) and put loop fittings on both ends. (You'll need two of these. One for each end of the element.) You'll need to notch the outer piece of the two part ceramic holders so the high temp wire can pass through where the holder parts come together without the wire getting pinched. I found a rod saw blade for a hacksaw frame works well for this. Got my rod saw blade at Home Depot. The next step is to drill hole in the sides of the reflector to allow the reflector to function as the holder for the new heating element. The new element ends up positioned an inch or two in front of where the original element is located, at about the same height. I've had the best luck drilling these holes with a step drill (unibit), but you can do the job using a series of twist drills , a light touch, and finishing enlarging the holes with a file.
Now for the assembly.
Attach extension wires to old heating element.
Insert new element in holes made in reflector.
Reassemble ceramic heating element holders and reflector, routing extension wires through notches you made in the holders.
Attach extension wires to studs of new heating element.
Your mod is complete and ready for testing.
Bear in mind that a dual element mod draws more power than the Bradley control system is rated for. I recommend you always use your PID, which carries a higher power rating, when operating your modified smoker. Also bear in mind that this mod will void your manufacturer's warranty. Some folks delay mods until their warranty has expired.
Last comment. Some of these instructions may be confusing until you have had a chance to remove the original heating element and study the parts that make up the assembly and study the pics that TedEbear provided.
Final suggestion, I promise. When you smoke your turkey, keep your vent wide open. Turkeys are large and they contain a lot of moisture. If your vent isn't open enough, moisture gets trapped in your smoker. The trapped moisture absorbs a lot of heat, so it prevents your smoker from getting back to your set temp after you put the bird in the smoker. I know this sounds a little counter-intuitive, but, open your vent.