Well the wideband o2 is an auxillary "added" sensor that only monitors your EG and sends its signal to the wideband gauge - it does not control anything in your car per say so tapping into it with an EFIE would be useless. I have yet to run my cell in my car to see what my wideband will show my guess is it will show CRAZY rich hehehehehehe
I am actually getting an AEM FIC to further control the fuel/ignition and timing maps on a laptop...I bet mr. scooby here can sing u a song about that