First check closely that base coat (the actual color of your car) is fine or it needs to be refresh too ?
Suppose if the base coat is fine then yes you can spray it with the clear coat.
Clear coat or lacquer has property to diffuse with its own layers. So technically you don’t need to be super careful while painting the clear coat.
If I have to refresh the clear coat of my vehicle, I will do following steps.
First wash the vehicle with car shampoo.
Then clay bar.
Then wash again.
Then dry
Then prepare for the clear coat (use newspapers, plastic bags, etc. to cover glass windows, wheels, etc.)
Then wipe it clean with Isopropyl alcohol.
Then spray the clear coat on it.
If you are doing with compressor machine, then technically it needs 12-24 hours to fully dry before 2nd coat.
If you are doing with spray cans, then it needs only 15-20 minutes to dry the top surface before 2nd coat.
Precausions: Paint job is not recommended to do in open atmosphere in countries like PK since we have huge amount of dust in air. But proper ventilation is must.
After coat is dry, grab your bare hand on it and feel the tiny/micro pumps on it. If you feel them, then grab 5000 grit sand paper and slightly rub it with water on the surface. Don’t rub it dry. Once done, project is complete. Go to Bundu Khan, buy 2 Kg Special Barfi and send me by post or bykiya 