I just had my car painted and the guy installed the fenders and aligned everything, but did not install the antenna prior to placing the fenders. Can you put the antenna on without taking the front fender off? I do not have the new antenna yet, but was wondering if there was a way to do it?

Sure, especially if you have help with skinny arms.

Protect the paint on the door edge and first several inches and back edge of fender and around the antenna cutout. Open the passenger door and slip the antenna into the opening after installing the underside mounting hardware. Feed it up through the hole and pull it up the rest of the way. Attach grommet and bezel and nut. Feed the antenna cable through the door jamb grommet, under the dash, and to the radio.