Buick 1994 Century Owner's Manual page 250

Cleaning Leather
Use a soft cloth with lukewarm water and a mild soap or
saddle soap.
For stubborn stains, use a mild solution of 10%
isopropyl alcohol (rubbing alcohol) and 90% water.
Never use oils, varnishes, solvent-based or abrasive
cleaners, furniture polish or shoe polish on leather.
Soiled leather should be cleaned immediately. If dirt
is allowed to work into finish, it can harm the
leather.
Cleaning the Top of the Instrument Panel
Use only mild soap and water to clean the top surfaces
of the instrument panel. Sprays containing silicones or
waxes may cause annoying reflections in the windshield
and even make it difficult to see through the windshield
under certain conditions.
Care of Safety Belts
Keep belts clean and dry.
Glass
Glass should be cleaned often. GM Glass Cleaner (GM
Part No. 1050427) or a liquid household glass cleaner
will remove normal tobacco smoke and dust films.
Don't use abrasive cleaners on glass, because they may
cause scratches. Avoid placing decals on the inside rear
window, since they may have to be scraped off later. If
abrasive cleaners are used on the inside of the rear
window, an electric defogger element may be damaged.
Any temporary license should not be attached across the
defogger grid.
248