o2 wire color help needed

[kennydawgg]

I dont have my service manual with me and i need a little help. I have a 98 spyder gs the front o2 sensor, I cut the wires to extend the harness but now that I look there is two back wires a blue and a white. Im not sure what black goes to the what black. anyone know if they are both grounds? or interchangeable? any help would be awesome