those newer vehicles usually had a return line on the radiator right under the upper radiator hose. you can take a 3/8" extension and stick it in the plug in the water pump to take it out and get the fitting... i don't know why they did that but whatever..
if you bypass the throttle body then you will have problems with cold starts. the fuel will not atomize as well and you will have to run richer to start up (by a LOT-- thus reducing fuel economy) and may damage your catalytic converters if you run them.
basically at startup everything is cold. the gas comes out in droplets and does not mix with the air very well... the coolant going through the throttle body or intake warms up the walls thus heating the air and helping the two "mix". colder air is denser and thus improves efficiency only if you have the proper amount of fuel mixed in with it. your computer also wont know you made any changes and without O2 sensors will never know that less of the fuel the injectors is spraying is actually atomizing and being burned. thus-- a lean mixture ... etc
if you are running all the factory equipment (02 sensors.. and cats) this may not cause any problems for you and you may end up with a little more power at the expense of wasted fuel on cold starts.
