I am interested in purchasing a Larsen Tri-band Antenna to mount on a Ford Van. My mounting options are to use a magnetic mount to attach to the roof of the van and run the cable thru the passenger door which hardly gets used or to buy an "L"bracket and attach it to my ladder rack. My question is would there be any difference in the mounting options as far as reception is concerned? I would think the mag mount would offer a better ground plane, but not sure. I plan on using it connected to my BCD396T. Any suggections would be helpful.