The answer is no if you are talking the windshield header which has the two rectangular cutouts for access to the wipers and windshield hinges, at least for domestically built cabs. It's welded in place to help support the roof and windshield.
Ford pickup bodies built outside the USA are constructed differently, so there may be a way to remove the header.
If you can post a picture of what you are wanting to accomplish and it might spur on some other ideas.