I'm considering getting a 2011 D440 and would be looking to make some mods right away before taking it off the floor. I'd throw on some BB7's and I'd like to run a 12-36 9 speed cassette in the back. My question is, would the stock rear derailure and shifter be compatible with this new cassette or would I need to swap that all out too? The reason I ask is because if I take in the components I want to throw on my shop gives me credits towards the parts I take off and don't want. Would I need a chain then as well? Obviously the less stuff I have to buy the better but I don't want to forget about something.