I have the antenna off on one of mine, it is 12.75 inches forward of the furthest back endpoint of the fender (3point corner of cowl,fender,hood) and 2.75 inches off the edge of the fender. it is 1.32 dia. with two round cutouts on each end inline with lengthwise of car the cutouts overall opening is 1.53 overall and are .13 wide. I took some pics and will try and post later today/tonight if I have time. My coupe has the bezel on it and it looks like it will measure the same too.