I used my JZA70 hydro fan cooler line for my steering line cooler since I used the 2JZGTE water pump setup.
This is better also because the Hydro fan cooler haves heat sinks on it and the opening on it is both on the same side since the steering pump and reservoir is on the same side this works perfect.
The only trick is to figure out how to mount it facing the other way.
Some people have used the Auto radiator bottom lines to go to it also when switching from auto to manuel.
I wouldnt do it myself because it transfers heat to the water system and also I have an after market koyo most after market radiators dont have the tranny coolers built in.