why not use this part: Firestik - QD4 - Quick Disconnect Stud Mount Item #: QD4
Firestik - QD4 - Quick Disconnect Stud Mount
Another "Firestik" first! You must have a stud mount when you're installing your antenna.If you also have your mind on a quick disconnect, now you can enjoy both functions in one part. These QD stud mounts are heavy-duty and ready to be attached to any antenna mount with the standard 1/2" (13mm) hole. They are specifically designed to accept any 3/8"-24 threaded antenna up to 5' (152cm) in length. The total height above the mounting surface is only 2.3" (58mm), or about one-half the height of using a K-1A on a standard stud mount. With a simple push and twist motion, your antenna can be removed from your vehicle.
Model QD-4 is for use with coax cables that are finished with ring type terminals. Both the ground and center lead connections are provided for on this mount. The QD-4 requires just 1/2" (13mm) on the underside so it is the perfect choice for tight areas.
