How do you remove the front over head speakers in a 97 freightliner semi?

Depends on which model Freightliner you have. If you have an FLD (120 or 132), you'll have to unscrew the panels they're mounted into in order to access them. It may involve removing multiple interior panels which overlap each other. If it's a Century Class, it should be much easier.. a lot of the times, the only thing holding those panels in place is the seal around the doors.