I see many pics of antennas mounted on the front bumper, what is the advantage? I have a Wrangler TJ with a Cobra 75 WX and a 4' Firestick mounted on the tire carrier, and even though the SWR is under 1.5, I never seem to get good reception, and need a lot of squelch. (Jeep has a hard top and Wilderness rack) Should I move the antenna or ?