We've all heard the discussions about the limitations of the GT rear end, especially in terms of engine swaps. I haven't heard any information on making the stock part stronger, or anything on how to help stock pieces handle more torque and horsepower without instant failure. I think I read that some of the people who race GTs have welded their differentials somehow. What is the net effect of welding, and does anyone have details? What else can you do to strengthen the rear end of the car?