The 5th nut should be on the driver side of the turbo..13MM..and is somewhat near to the lower bolt of where the TB/Turbo bolt is that you removed.....What oil like are you talking about?
The old FEED line is the one that is on the top, and that I just used a reg line wrench on...the oil RETURN line just lays in a grommit in the intake, and that does not need to be removed for the turbo to come out.