Just get the newest book that you can, and there won't be too much difference.
Try reading it first though the haynes might be easier for you to understand than Chilton.
About your oxy sensor.
There are 2 or more all located in your exhaust system.
Look for a little sensor in the exhaust with some wires going to it. They are easy to find
Here's some bad news though. They are often basicly rust welded on to the point that they require an oxy acetlene torch to heat the metal right around there to remove.
Try to remove them first, but don't be suprised if they don't come out and you have to take them to a shop to change.
A plumbers propane torch won't get hot enough, and unless you have worked with an oxy acetlene torch you'll probably burn through the exhaust. That is saying that you can even borrow or rent one.