The following image is from the 1957 Pontiac Dealer's book. The Dealer's book was apparently published before the Custom 4-dr Safari (Transcontinental) was released. Note that these upholstery options were available on the Catalina (hardtop) Star Chiefs also.

This is the list of Trim Codes from the 1960 Pontiac Master Parts Catalog.  Model 2762SDF-64DF is the Custom 4-dr Safari and the Custom 2-dr Safari.  So, the Custom 4-dr Safari was offered with the same upholstery material and colors.