I'm looking for the location of the ECM in a 97' f150 5.4.. Also need to know difficulty on replacing it and is it what controls the windshield wipers and windows?

 

The ECM does not control anything but the motor and transmission.
If the motor run ok, leave it alone.
Another module called the GEM located on the rear of the incab fuse panel, does the wipers and windows.
Good luck.