I applied 303 fabric guard (2 bottle kit) when I bought the car in 2017 and its
still going strong 4-1/2 years later. Car is garaged. If I let it outside at this point, I would do another two coats beforehand.
Detailed instructions here:
https://www.camaro6.com/forums/showt...5#post10171125
TL/DR: Follow the directions on the kit. But roll it on, don't spray it!