There has been some recent discussion about the convertible specific floor reinforcement plate or "torque plate" as it has been referred to with respect to clearance for dual exhaust. While surfing another forum I saw a CNC version of the plate which incorporates an offset flange to increase the tunnel clearance. Thought someone might find this useful in the future.
http://www.16w.biz/#!projects/clui
http://www.16w.biz/#!projects/clui