Galaxy DX 959

Just got a DX 959 installed it with a k-40 ( 3500 ) cb antenna and new cable the SWR are still high the red lit is not on but on 1, 20 , 40 they are almost on red. Here is the question what is the best way to ground the antenna? do i have to ground the radio as well? it sits on plastic/fiber glass. i drive 2004 Columbia class

 

in radio meter and mirror mounted antenna on external mount. swr on 1 is 1.9 and on 40 is 2.8 almost 3.

 

doing it just like in the book. it should be self adjustable on that radio kind of did it to double check. now same radio same antenna in the different truck and his swr are below 1.5 mark on the meter.