GMC 1996 Suburban Owner's Manual page 250

Stow the flat tire in the cargo area of two-door Utility
and Suburban models and secure it to the tire carrier.
To
stow the flat tire:
1.
2.
3.
4.
5.
Put the cover back on the tire if your vehicle has
one.
Put the flat tire in the cargo area of the vehicle, over
the retainer bolt.
Slide the adapter onto the bolt in the proper location
for your model and put the wing nut on.
Turn the wing nut clockwise until the adapter is tight
and secure against the wheel.
Close the tire cover, if you have one.
Spare Tire
--
Two-Door Utility Model
1. Carrier
2. J-Bolt
3. Adapter
4. Spare Tire
5. Nut
6. Cover
7. Pins
8. J-Bolt
9. Use Upper Hole and Pin for P265
Tire or Lower Hole and Pin for
LT225/245, P245 and P235 Tires
Be sure the J-bolt is hooked properly for your model or
tire size as shown.