1999 Buick Riviera Owner's Manual - Page 228
1999 Buick Riviera Manual
Page 228 highlights
yellowblue Storing the Spare Tire and Tools CAUTION: Storing a jack, a tire or other equipment in the passenger compartment of the vehicle could cause injury. In a sudden stop or collision, loose equipment could strike someone. Store all these in the proper place. Store the compact spare tire and tools as shown in the diagram. The compact spare is for temporary use only. Replace the compact spare tire with a full size tire as soon as you can. See "Compact Spare Tire" later in this section. 5-26