The X-pipe should be placed as far forward as possible, since the front of the driveshaft has the least up-and-down movement. To angle the collector extensions into the X-pipe, they were cut right after the crossmember, before being tack-welded to a 45-degree section of pipe. For the sake of simplicity, cuts should be made in increments of 15 degrees, which make it easier to keep the longer sections of pipe parallel to the framerails. Eggen says that if cuts are made at odd angles, such as at 43 or 41 degrees, then the intermediate pipe will have a tendency to point inward or outward as opposed to going straight back toward the rear bumper. When possible, 45- and 90-degree angles are ideal.