Replacing PS lines
 

I'm attempting to replace the PS lines in my '87 DeVille due to old age of the rubber hoses. Bought both lines from RockAuto...Edleman brand. First problem I've run into is the method of installing the return line. The only way I can see it going in is from over the top of the engine. The OEM line had a saddle-bend around the O2 sensor, but the replacement line doesn't. Has anyone done this job and can confirm the 'over the top of the engine' installation method is correct?
Second question: the pressure-hose connection at the gear. 18mm is what I measure, but what tool is needed to loosen that nut? No room for an open-end wrench. Is the correct tool a crow-foot wrench? I can't find any useful info in the FSM, so I hoped some folks here had some insight. Thank you