CB with rfx 150 install

A 7 ft antenna? Wow.....that will be tall on a Cascadia! I know the 5.5 Francis if stood straight up was over 13'6.
Angled forward kept it even with the top of the sleeper and helped compensate for the wind bending it back at highway speed.
I used it with 18ft on mini 8 coax and had about a perfect SWR.

 

I hear ya link! I just remember the 5.5 looked tall on my old truck...It worked very well though.
I think fiberglass is the way to go on those trucks.....even a top load tall fiberglass would probably work good too.

 

bird perch mounts at about 6 feet, 7 foot antenna would keep you under 13'6. you would be smacking some branches where they are not well trimmed same ones you hit with your sleeper if you have a condo.