I am using a hydraulic floor jack and the owners manual says to put the jack under the arrows on the side trim. The plate on the jack is much larger than the one that comes with the car. Are the labeled spots only to be used when I have the factory supplied jack? Should I look for a stronger area when using the floor jack? Where is the best spot to place jack stands?

 

You can jack it up form there.Most shops lift it from that point with the lift.
For the jack stands depends on what you are doing.If you are going to remove the axle or something like that use around the jack point.If you are going to change the oil you can use anything solid.