[SCOTI]

The notched portion of the c.member was necessary because I wanted exhaust all the way to the rear bumper (I dis-like how turn downs stir up dust/dirt).

Since my bed floor will be raised 3" above the frame rails, the notches allow for routing of exhaust over the c.member (going under gets it too close to the rear axle) w/plenty of clearance (no rattles). This routing choice also required notching the Panhard bar triangulation c.member so that the exhaust can drop back down before the gas tank (69-72 Blazer tank).

As you can see, this mod allowed almost 4.25" between the c.member & bed-floor & just over 4.5" between the PHB c.member & gas tank lip. Some 2.5" pipe should route through there w/no problems.....