Water pump replacement

[M Shakespeare]

My water pump has failed (2005 C6 LS2) and i just wanted to ask for some advice on how easy the job is. I'm sure there are plenty of members on here who have carried out a replacement themselves. How easy/time consuming is the job and how many associated parts are worth replacing whilst doing the job.
I'm going to make a Rockauto order so wanted to check I order everything together.
Thanks