OK, so I have searched a ton, read a ton, and have troubleshot a ton....
2006 Tacoma with Fiberglass cab high camper shell,
Cobra 75 WXST, 18' firestik coax, stainless hood channel mount, 3' wilson
I also have a second coax, 4' firestik, and another mount in the bed that I used prior to the topper....
Long story short, my SWR is very high (in the red, 5 to 10). I have good ground showing using my multi-meter. All continuity is where it should and/or shouldn't be. I have tried both mounting locations with both antennae and both coax. My next step will be to try the Cobra 29ltd. It does have a built in SWR, not that I ever even knew it... LOL!!!
Now, I don't have the paint scraped off under the mounts, should I?
I do have marginally better SWR once in a while, for apparently no reason, the best I have seen is ch1=5, ch40=3.
In the past, I just hooked up the CB and slapped on the antennae, never tuned with an SWR meter, and just went with it. Never had a single problem with several different radio's and different mounts. The mount in the back of the bed (painted metal just inside the tailgate) with a Cobra 29ltd had awesome range (compared to several other people I knew with jeeps and other units). Was I just lucky?
I am quite frustrated at this point, and just about to say the heck with it, and just roll....I am sick of messing with it.