The first part of the configuration is really easy, go into the /usr/src/fbbsrc.704j directory and give the following command
./install_sh
This will create all the required directories and move your newly built executables into the /usr/local/sbin directory
The next step is to move into /usr/local/sbin and give the command fbb
This should ask you some questions, build the config files, then start the BBS...
BUT IT DOESN'T because of an error in the way the file is written and you need to correct it.
The install program puts the fbb executables in the /usr/local/sbin directory, but if you look in the file called fbb in the /usr/local/sbin directory you will see it is set to the wrong directory, it says SBINDIR=$DESTDIR/usr/sbin you can open the file called fbb with any text editor and change it to read SBINDIR=$DESTDIR/usr/local/sbin then when you give the command fbb the BBS should start up properly with no errors.