setting swr

I purchased a new cb and magnetic mount wilson antenna. When i keyed the mic I noticed an antenna warning. I checked the swr on the antenna and it was way off. I started on chanel 1 then 40 to match them up. I was able to get them pretty close but, they are both in the red however, in the middle chanels I am between 1 and 1.5 so I think I got it tuned about as good as I am able to do it. I suppose the best thing to do is stay away from the chanels on the ends. If anyone has any advice i would appreciate it.

 

It is a lil wilson antenna mounted on little shi*box car. I have it basically in center of roof. I think it will be ok as long as i stay away from the channels at the ends of the radio. I should check to see where the major problems start. I think i can fine tune it a little better. Less than 1.5 is pretty good thru middle chanels though i dont want to mess with it much and make it worse thru the mid channels