I have cut open the one bitbill and have the private key. I have registered with Mtgox with the username "ThisIsBTC123". Do I simply click trade, sell bitcoins, click add more (next to GBP in your account) and then under the add funds heading select "redeem private key" from the dropdown box? I assume this part gets the bit coins into my Mtgox account?

Once the bitcoins are in the Mtgox account and have been sold do I just request a withdraw after than (bank transfer)?

Thank you all!