I just installed a Cobra 75 with a 4 ft. Wilson Firestick. I have tuned the antenna, but my best SWR reading is: 2:1 on channel 1 and 2:5 on channel 19. This was done after moving my ground...before that, the readings were horrid! Is this reading suitable? As I see on the instructions, these readings should be a max of 2:1. Does the higher reading just shorten the distance of transmission and receiving? What can I expect? Can I do anything else to improve the readings? I have already removed the tip...so I can't get any better with that. Thanks in advance.