A roof rail assembly for a vehicle that includes a body side outer and an interior trim piece connected to the body side outer. This invention is further directed to methods and systems for making and using inferential networks. A partition wall is disposed to divide the separator chamber into an inlet chamber at side of the blowby gas inlet and an outlet chamber at side of the blowby gas outlet. Each shell member is comprised of a high-strength, pliable material permitting shell members of different sizes to be connected together in a single casing spacer to accommodate a wide range of carrier pipe circumferences. As in the case of the first payload, the hold downs adjacent to the top end of this next payload are rotated to their closed position. Two analog-to-digital converters provide a respective digital signal representative of the output of the mixers.