What EEC are you using? If stock then you need to leave the stock O2 sensors in.
I use to run a megasquirt with the LC-1. I had wired the stuff going to the ecu through the stock O2 wiring. I took an old O2 sensor and cut of the plug. Then wired the LC-1 into that. You should be able to get power, ground, heater, and signal.
I did it this was so I could easily switch back to the stock EEC if need be, like I've now done. Its been awhile since I did and removed the LC-1, so I am trying to work off memory.