I used a 2' fire stick for my AM/FM radio, but not relocated like you want to do. I started out with this kit from Qtec:
Quadratec Exclusive JK-ANT - CB Style AM/FM Radio Antenna for 07-13 Jeep® Wrangler & Wrangler Unlimited JK - Quadratec
which gives you a stud, cap an 4' cb styled antenna.
When I installed my CB, I ordered a 2 pack of 2' Firestick antennas from Ebay. Since I had the extra one, I swapped out the CB styled antenna for the 2' Fire stick and it worked fine for me.
I've read that I should have problems, but I never did. If you live out in a rural area, you may have reception problems, especially AM radio, but I never had an issue.
You are going to need the antenna and mount and coax cable (of course) then something like this:
Amazon.com: Truckspec 10feet AM/FM Antenna Coaxial Cable RG-58A/U Coax With PL-259 To Motorola Plug TS-307C: Electronics
The coax is only 10 foot, so you'll probably need an extension. You can use the regulat 18 foot CB Coax with some sort of CB to AM/FM adapter/splitter like this:
Amazon.com : Firestik AR-1A Splitter CB AM FM Radio Audio Stereo Antenna Tuner Match Maker : Electronics
If you are using the stock radio, you'll also need (I think it's this one);
http://www.amazon.com/Metra-40-EU20...2038&sr=8-63&keywords=jeep+radio+adapter[/URL
Quadratec Exclusive JK-ANT - CB Style AM/FM Radio Antenna for 07-13 Jeep® Wrangler & Wrangler Unlimited JK - Quadratec
which gives you a stud, cap an 4' cb styled antenna.
When I installed my CB, I ordered a 2 pack of 2' Firestick antennas from Ebay. Since I had the extra one, I swapped out the CB styled antenna for the 2' Fire stick and it worked fine for me.

I've read that I should have problems, but I never did. If you live out in a rural area, you may have reception problems, especially AM radio, but I never had an issue.
You are going to need the antenna and mount and coax cable (of course) then something like this:
Amazon.com: Truckspec 10feet AM/FM Antenna Coaxial Cable RG-58A/U Coax With PL-259 To Motorola Plug TS-307C: Electronics
The coax is only 10 foot, so you'll probably need an extension. You can use the regulat 18 foot CB Coax with some sort of CB to AM/FM adapter/splitter like this:
Amazon.com : Firestik AR-1A Splitter CB AM FM Radio Audio Stereo Antenna Tuner Match Maker : Electronics
If you are using the stock radio, you'll also need (I think it's this one);
http://www.amazon.com/Metra-40-EU20...2038&sr=8-63&keywords=jeep+radio+adapter[/URL