R.P.O. (regular production option) Z62 = Custom Comfort Option:
The custom comfort option is available for all Series C-K-L-M10 through 80 cabs and includes the following:
Left armrest - A steel reinforced, molded polyurethane foam armrest of unitized design is covered with embossed vinyls. Red vinyl is used on trucks with red, white or gray exteriors. Fawn is used with all other exteriors. A matching armrest for the right side is available as a dealer -installed custom feature.
Right sunshade - Matches the standard medium Fawn left sunshade. Both can be pivoted for use at the side windows.
Chromed cigar lighter - Automatic pop-out type.
Full-depth foam seat - The full-depth foam seat is included in the custom comfort option. This seat construction with standard upholstery is also available as a separate option a extra cost. A urethane foam seat cushion, approximately 6 inches thick, covered with a cotton pad gives the maximum in riding comfort. The comfort of the backrest is also increased by the use of urethane foam and cotton pads over the coil spring construction. With the custom comfort option, both seat and backrest are upholstered in luxurious nylon-faced cloth having a medium and dark Fawn pattern with red and gold highlights. Red vinyl is used for the facings and bolsters with red, white or gray exteriors. Medium Fawn vinyl facings and bosters are used with all other exterior colors. The backrest insert is white vinyl.
Special insulation - Includes full undercoating of cab floor and a thick woven cotton fiber pad for the underside of the cowl chamber. Effectively reduces noise level and provides heat insulation.
This information is from the Truck Sales Data book.