I was just commenting to my wife about how there are so many similarities between the sailboat forums I frequent and the trailer forums. Electrical systems, etc..
There's a product that's popular with boaters for dealing with chalked, faded fiberglass. Suggest you look into Poliglow. There will be plenty of info available, including a lot of Youtube videos.
The best way to deal with the fading is to do PROPER compounding and polishing followed by the sealer/wax of your choice.
Poliglow is a step saving process that is a substitute for compounding. Basically, you use their prep products and then wipe on several coats of their product. Results are quite good, and it can last several years, particularly in northern climates. See what you think.