migration assistant from mac to mac

I'm trying to use Migration Assistant to transfer my files from my old computer (PowerPC G5) to my new mac mini. I have them connected with FireWire. I looked at the online instructions, and it seems like i need to have both hooked up to a monitor and keyboard to do this??? if i used an ethernet cord instead would that work? (of course, i don't have an ethernet cord, so i'm hoping this isn't the case.)

I'm not sure if Migration Assistant isn't locating the other computer because of the above, or if my old computer is that far gone that it's not working correctly. Please help before I panic! thank you!!!