CB Antenna Question

I've been using a magnetic base antenna for years. I just ordered a Wilson Flex 3' antenna. I keep my fiberglass shell on my truck year-round. I'm wondering if a rear mount would work for my new antenna, or if I need to do a ditch light type mount. I don't know if the fiberglass will interfere with the signal or not. I'm considering a rear bolt on bracket on the corner where the tailgate closes.

Thanks!

 

@WileECoyote

 

Bump for those who will see it at work tomorrow.

 

ideally you want a metal plane under the CB

 

Under the antenna? Does this amplify the signal? I've been using them off and on my whole life, but really have little understanding. I'm guessing you recommend the hood mount then. This was the original plan, and the reason for going with the Wilson Flex. I drive in tight trees quite a bit and have broken a couple firesticks on work trucks in the past. I've read the Wilson's hold up better.

 

Yes under the antenna, as to why it's needed it's kind of a complicated thing to explain which honestly I dont 100% understand and couldnt explain well anyways. But without the ground the performance will suffer a bit. I was having high SWR issues, and once I made the switch to the hood my SWR instantly dropped without me even adjusting the antenna. I recall I was getting like 1.2SWR on the channel I tunned the antenna for, and 1.5 on the worst channel.