The pressure line would usually only have high pressure when the pump is running.
After it was shut off for a while pressure will decrease.
Fluid should be drained , it is easier to drain when you loosen one of the bottom PS hoses.
You will need to put the car up on jack stands or ramps if you can get it on those.
Most ramps hit the front bumper though
Bleeding the system of air is another thing that can be difficult.
I wrote a procedure for this in the
Tips and Maintenance .
Here's that link,
Bleeding your Grand am's Powersteering
Good Luck
ps a line wrench works best removing these lines.
