Converting from manual antenna to power antenna

Hi guys,
I would like to convert my sedan's manual antenna which is located on the front left pillar to power antenna located at the rear left (near the fuel door).
The problem is, I don't know the exact location where to install the power antenna. I would like to have the installation as accurate as possible. Can you guys help me?
Thanks.
I would like to convert my sedan's manual antenna which is located on the front left pillar to power antenna located at the rear left (near the fuel door).
The problem is, I don't know the exact location where to install the power antenna. I would like to have the installation as accurate as possible. Can you guys help me?
Thanks.