tanahara

I am thinking about buying a Garret turbo a/r .50 of a fellow member for my 1jzgte im about to install, i know the stock is not going to be what i want and i have a little bit of money to throw around and hes come down to a good price i think for it. I am wondering what all i need to upgrade for it to use the turbo efficiently and also what to put together to form a kit for it. I appreciate your input guys you all have been super helpful to me in the past thank you.