Where does the O2 Sensor go

My service engine soon light has come on in my 1996 S-10. and I took it to the Auto Parts store which read the code and told me it was the O2 sensor. The engine is a 4.3 liter Vortec engine. I am looking to buy this part and put it in myself if someone can tell me where it is located and how hard it is to put it in. Thanks for your help.

On my 98 S10 there are 3 O2 sensors,2 before the cat and 1 behind it.The 2 before the cat are located at the end of the exhaust manifold.Did the code reader tell you which one?Like "Bank 1"for example.

Before you buy it try cracking the threads loose.
The reason why I say this is they often rust weld themselves on so you might have to take it in a shop and get them to take it off.
They just use an oxy-acetlene torch, heat it up and let it cool. They usually come right out then, but if you get it too hot you'll burn a hole in the exhaust system

Before you buy it try cracking the threads loose.
The reason why I say this is they often rust weld themselves on so you might have to take it in a shop and get them to take it off.
They just use an oxy-acetlene torch, heat it up and let it cool. They usually come right out then, but if you get it too hot you'll burn a hole in the exhaust system
The one after my cat was like that,had to get her cherry before she came out.

Take it to a place that knows what the hell they are doing, i spent 8 hours waiting. after 4 hours, "gee that thing is on there good".... yes you country bumpkin thats why i took to to your shop. If you do take it in, buy the part and have it installed. much cheaper