OK so I install my cobra 25 lx and I am getting the awesome dash lights/ wiper goes off issue. My question is, The mount is onto my spare tire carrier. From what I read this isn't grounded. So are the bolts that hold on the spare tire carrier grouded?

 

No, the tailgate itself isnt grounded, it is insulated by the bushing on which it rides, you need to at least ground your tailgate to the tub of the jeep, but it is better if you ground your antenna or mount directly.

 

Bond your tailgate to the frame of your Jeep.
to do this Use a couple ground braids and run one from the tailgate to a bolt by the speakers/roll bar, then take a braid and run it from the body to the frame. Use star washers to get a good connection. on the frame drill and tap and use star washer...

here is my tailgate and rear body to frame bonding...
I have two straps running from my tailgate to a secured location, Hinged side..


I also have one here...


body to frame bond... I have one on each side of the rear of the Jeep..



if this doesn't completely fix the RFI,, try running another 1" ground braid in parallel with the OEM one, from the engine wall behind battery to the engine.. I had to do that for higher power HAM comm.
the OEM one is the thin one behind the big one.... I installed it approx where the OEM one went... I connected it to a ground by the battery...



engine bond by the battery



these are a few areas I had to do in order to use 100W HAM bands....

 

Thanks for the photos and explanation showing exactly where you attached the ground straps.

As for the original poster, I'm assuming you tuned the antenna with an SWR meter inline and re-calibrated the meter every time you adjusted the antenna till you had an acceptable SWR.

Also it wouldn't hurt to try grounding the cobra 75 connector box. I would also use a coax ferrite choke.