We cut the old exhaust off and pulled the oil pan. A 1-inch hole will need to be drilled in the oil pan for the 9/16-inch (AN-10) oil return line from the turbo. We opted to weld the AN-10 fitting in, but you can simply bolt it through the oil pan. Either way, unless you want metal shavings in your oil, pulling the pan is needed. Since we had RTV'd the old oil pan gasket on, we replaced the gasket with a Fel-Pro part (PN OS 34007 R). Most can do without this, as the oil pan gasket is often reusable.