It's directly behind and below the alternator. There is a black cap with white lettering and a white picture of a steering wheel. If you need to fill it, I would suggest a long funnel or funnel/hose. Good luck :P
At the power steering pump reservoir. The power steering pump or reservoir is located on the left side of the engine between the engine and the firewall
At the front of the engine , towards the drivers side of the engine ( power steering fluid reservoir on a 1998 Mercury Grand Marquis )
eny power steering fluid will work
Into the power steering reservoir.
The power steering reservoir is underneath the alternator by the firewall.
where to put power steering in a 2007 Pontiac gran prix
It is part of the power steering pump assembly.
I was looking at a picture in the 2003 Mercury Grand Marquis Owner Guide and it shows the power steering fluid reservoir at the front of the engine compartment between the engine coolant reservoir and the engine air filter box
With the engine off, remove the power steering reservoir cap, and read the fluid level.
The power steering reservoir is in a tough location on this car. It is located at the passenger side, rear of the motor, next to the firewall. The two heater hoses are almost right on top of the cap. You will need a long, bendable funnel to be able to add fluid if need be to reach the reservoir.
Link with picture of where steering fluid goes: http://www.fixya.com/cars/t1612500-power_steering_fluid
A person adds power steering fluid under the hood of the car to the power steering fluid reservoir. It is labeled power steering, on a yellow twist cap.