Heres an update so far, I'd welcome comments, what I want to know is was the way I did it the best way. What I did for the hole was to use split polygon to split the sections on the bottom half of the top, then added some vertex pts and shaped it into the shape I wanted, then deleted the faces, is this an acceptable way to do it ? I'd like to learn the right techniques for doing things, in case I need to do something later which required me to do it another way, etc etc...

Also how do I go about fixing that line across the top of the can which appeared after I'd altered the edges to the shape of the hole, the texture on top is blinn at the moment. Thanks.