Yeah the objective tracker can be wonky.
Seerah's solution is currently the best imo.
http://www.wowinterface.com/download...herWabbit.html
Basically you create a new frame and position/scale/size it to whatever you want. You reparent the ObjectiveTracker to that frame attach a point (like TOPRIGHT) and set the size to equal the size of your new frame.
You have to track every event that moves the objective tracker and keep it in place.