I have a 72 cutlass sup the antenna is not securely fastened, it is very loose, does not stick straight up kinda off to the side, has somthing come loose from underneath? Can the antenna be worked on without removing fender? also I am missing the rubber gasket that goes on the external part of the antenna, any idea where I can get one?

 

I'm pretty sure a windshield antenna is standard equipment on those so it shouldn't have an external antenna?
Does your windshield have thin wires running up the middle of it in the glass?

 

The 72 Supreme (to my knowledge) did not come with a mast antenna - just the windshield antenna. Since those do not work that great, many owners install aftermarket masts. I am pretty sure this is what you have.
Since these are all different, repair procedures will differ. A posted picture would help. Some have bezels on top that can be tightened, some have screws under the top bezel, some have a nut below the top bezel, etc.
Getting inside the front fenders can be a pain, so hopefully that is not needed. Most should be adjustable from up top.

Replacement parts would need to be either made, or improvised for aftermarket units.
IF you do decide to replce it, look for one where the mast can be removed - handy for car washes or covering the car.

 

thanks have to look to see if it has a window antenna, I can tell you it has an aftermarket radio so maybe the antenna is aftermarket as well, have to look at it further. will try to post a pic.

 

Many times the antenna wire connector at the base of the windshield breaks, requiring the addition of another antenna. This had happened to mine long ago before i bought it, so the guy put in a power antenna in the rear right quarter...
He was also a CB buff, so it had to be a good unit.