Finally changed out that nipple. The original snapped in half right at the edge of the groove for the o-ring. If you ask me, it is a very poor design to construct an elbow where it gets so hot and it's connected to a hose which can create tension and torque the elbow causing it snap. In addition the groove for the o-ring molded in has sharp corners rather than a rounded groove, weaking the part.
But all in all it didn't go too bad. The only bad thing was when trying to remove the broken piece that was stuck in the radiator, I accidentally pushed it into the radiator (the black side tank/manifold). Damn! I had to take the radiator out to turn it upside down and dump the little piece out through the coolant inlet. That was not an easy task since it is so tight in there. The automatic transmission cooling lines should probably be disconnected to make it easier to remove the raidiator, but I didn't know the best way to remove those lines without damaging them.