I'm looking for cable recommendations for a mobile install. I'm mounting a 1/4 wave dual band antenna on the driver's side rear stake pocket of my truck. I'm going to route the cable along the frame where it exits the truck bed, and through the firewall into the cab, probably about a 15' run. Which type of cable will be the better one for this install, considering that it will be exposed to moisture under the truck? Thanks for your help.