Experience changing 3.4 DOHC O2 sensors?

[Upgrade]

I bought new sensors for my 3.4 Lumina LS and I wanted a little insight from those who have done it before. I know that the downstream sensor will be cake as it sits right out in the open. I also understand it from conversation with the dealer mechanics that the upstream sensor is much harder to access. Does anyone have any tips or suggestions to offer before I dig into this thing? Other than the correct O2 socket are there any other tools I might need? I am going to be using a well stocked Hobby shop here on Fort Drum complete with lift. Thanks.