Acceptable SWR readings or keeping tuning? ch1=2, ch40=1.5

I'm asking because 1. I actually purchased the swr meter and did the readings myself and electronics are not my thing. I put a SWR meter to my antenna/CB and got a smudge(very minuscule) 2 on channel 1 and 1.5 on channel 40. Are these acceptable to use? or should I keep tuning. I know you should try to even the ratio between to two channels but when I try to short the antenna to get channel 1 down, channel 40 changes. I parked in the middle of an empty college parking lot and spent 30 min try to get both channels to match almost perfectly. I purchased the Rugged Ridge antenna mount that mounts over the tire. I didn't scrape the powder coat off and can do that Monday but if these are acceptable numbers, sounds like it will be fine. Cobra 19DXIV and 3'firestik is what I use. I used the teraflex on a previous CB and it was powder coated and I never scraped it off and the CB worked.

Not sure on mount. I installed mine on the corner of the tramp stamp. I did not remove the powder coating at first and the swr reading were super high. In the 4-5 range. I read about needing a ground plane. So I removed the bracket took the sanding wheel to where the two bolts mount the bracket to the tailgate and then the bottom side of the antenna mount removing the powder coating. That dropped swr to the 2-3 range across the 40 channels. I was able to fine tune everything to about 1.25

Check out right channel radios they have a section that explains everything.