Lexus 2003 LS Owner's Manual page 322

IN CASE OF AN EMERGENCY
40L053a
To remove the spare tire:
1 Remove the spare tire cover.
2 Loosen the bolt and remove it.
When storing the spare tire, place it with the inner side of the
wheel facing up. Then bolt the tire in place and install the spare
tire cover to prevent the tire from flying forward during a
collision or sudden braking.
308
40L150a
2. Block the wheel diagonally opposite the flat tire to keep
the vehicle from rolling when it is jacked up.
When blocking a wheel, place a wheel block in front of one of
the front wheels or behind one of the rear wheels.