U-bend replaced, SES light

I recently got a 97 GTP that allready had the resonator and u-bend replaced. the SES is constantly on becuase the guy i got it from was to lazy to put on a O2 simulator. Is this hard to do and expensive, what if there is not place to put ot or the harness for it is gone. Im asking this becuase i think the dude just welded a 3 inch straight pipe in place of the u-bend and did not weld on a 02 bung or place to mount it, and i have no idea if he left the harness in there. I want to fix this so if something is wrong i will get a genuine SES light, instead of it being tripped up indefinatly becuase of a missing o2 sensor. And yes i got a new INTENSE PCM but did not want to pay an extra hundred dollars for the custom PCM to have them program it out of the PCM.

The O2 simulator simply plugs into the wiring for the old sensor. They aren't very expensive I think they run about 50 bucks. If the harness is not there you will need to try to find the wiring and replace the plug so you can plug the simulator in. You don't need the bung on the pipe. Once you put the O2 simulator on you should get the code cleared, may even clear itself and you should be good to go.

This O2 sim is a good one and they dont have problems with them like the one from ZZP,which keeps tripping the SES.

Once you plug it in,with in a few driving cycles it should shut down the SES.Im sure the harness is still there and there is a cover that holds the harness in,next to the exhaust.

http://www.3800performance.com/Merchant2/graphics/00000001/O2_sim.jpg

http://www.3800performance.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=O2-SIM&Category_Code=ES_H&Product_Count=14