You don't. A 1991 Cavalier did not come with airbags.
Behind the glove compartment.
You don't, you replace it.
Around 2300-2500 lbs
Check the fuse box.
Chevy dealer, auto parts store, etc.
On the right side of the fuse box
The refrigerant capacity of a 1991 Chevrolet Cavalier is 36 ounces of R-12 Freon. This is the same for all Cavaliers produced from 1986 to 1993.
Was built for R12, should be converted to R134a