Extracts from Model Train Journal :
From the 1970's, Custom Services, aka Clark Benson, via LSSAE and magazine ads, line of 20 inch aluminum Budd style extrusions of passenger cars with milled windows to match various lightweight cars from other builders.
Lionel pattern extrusions with the resulting kits retaining the shallow, simulated wide diaphragm end caps of the original Lionel 15 inch cars as well as the name plate gap in the lower panel fluting. The same basic arrangement has/is unfortunately been offered by at least Weaver and Williams albeit sans the fluting gap.
Cars sold at three price levels; a blank extrusion with end parts as a Scratch Builder's Kit, a milled window car-body allegedly representing the listed prototype, and the same built up to various stages of completion depending on the buyers budget. Though neither as expensive nor as accurate as the more prototypical MAC Shops offerings, they were not cheap for the time either. These have not fared that well price wise as the hobby has evolved with the explosion of Chinese made finer scale offerings.
Clark A Benson Custom Services box