I believe that during install Fedora uses anaconda for configuration. I do not think you can use it post install..
If you just want to make the card active on boot, just edit the config file..
: First Ethernet card configuration file
: Second Ethernet card configuration file
To edit/create first NIC file, type command:
# vi ifcfg-eth0
Append/modify as follows:
# Intel Corporation 82573E Gigabit Ethernet Controller (Copper)
taken from http://www.cyberciti.biz/faq/rhel-ce...configuration/