instructions
My instructions from DT tell you how to do this, didn't the shop that installed it read or do they know what they're doing. If you have the instructions read through them and its pretty simple. I'm not sure what everyone calls it but there is a slip joint on the steering link coming from the box, there is 2 clamps on each end of the slip joint, loosing these 2 clamps and turn the slip joint by hand or you might have to put a screw driver in the slot, it turns either direction, it will either lengthen the steering link or shorten it. Make sure your tires are straight, then start by turning in which ever direction, look at the steering wheel if it is further off then turn the joint the other direction, keep turning it until your wheel is straight, then tighten the clamps on each end back down. Now your wheels should be straight and your steering wheel straight. Hope this helps a little if you need a pic let me know and I'll work on one for you.
Locate your steering box, find drag link, follow steering link down until you see the slip joint, loosen clamps, turn until straight, re-tighten clamps. Good luck... ... .
Another suggestion since they did not straighten out your wheel I would make sure they even centered your axle when installing the DT bar. Measure each side they shoud be the same, there is a tool with the trac bar to do this it is also explained in the instructions, good luck.