If the AC system needs recharging, you cannot use R-12. Instead, you'll need to have the system converted to use a compatible refrigerant like R-134a. This requires more than just a refrigerant change; it typically involves flushing the system, replacing the drier (accumulator), and possibly other components depending on the condition of the system. Using R-134a in an R-12 system without these modifications can severely damage the system.
Therefore, you should take your Camaro to a qualified AC repair shop. They can properly assess the system, perform the necessary conversions (if needed), and recharge it with the correct refrigerant (R-134a).
