Freeze plug location

Unless they are leaking or you know they will be leaking soon you do not normally change them unless you have the engine out of the vehicle or they are leaking as they are not considered a maintenance item.
However, they are not real hard to change depending on which engine you actually have.
Why do you want to change them and which engine and transmission do you have?

The Zepher/Fairmont did not have a V6, it did have an inline six though. There is not a real "simple" way to change them. They are a pain because of the place they are located. You start by draining all of the engine coolant, plus removing the block drains. Then you need to strip off most of the parts on the passenger side, the exhaust manifold and the AC and anything else on that side. Then you can knock out the old plugs, clean out the holes and install the new ones. Use brass plugs and you will not need to do them again.

It is easier to actually pull the engine out of the car and then change them because you have better access, plus there is one that is on the rear of the block that you cannot get to with the engine in the vehicle.

This is one video that shows the process. As I said it is not easy.
https://www.youtube.com/watch?v=C5WvAvFz8c0

There are tools you can get to install them in hard to get to spots but it still needs room to work. In this case the ones in the rear of the engine would still be out of reach with the engine installed.