To remove wax staining from matte vinyl, try using
Brilliant Glaze. Rub it into the stained area, then wipe with a microfiber towel. If that does not fix it, then use diluted
All Purpose Cleaner (1:1) sprayed onto a MF towel and then gently scrub. Rinse the area immediately, do not let the All Purpose Cleaner dry on the vinyl or paint. Do not work in the sun, make sure the surface is cool to the touch.
Make sure that any car shampoo you use does not contain any wax, the same goes for any spray on waxes, as they will lead to build-up and staining on matte vinyl.
Adam's Quick Sealant is a great product to use on the textured plastic trim pieces. You can also use Quick Sealant on the matte vinyl, just make sure you apply it and level it as shown in the product video. Quick Sealant is optically clear and leaves no residue behind. It lasts a long time and won't wash off as long as you use a balanced
Car Wash Shampoo.
Also, for a daily driven truck, you are better off using a paint sealant than a wax, as the sealant will last about twice as long as a traditional carnuba paste wax.
Adam's Liquid Paint Sealant is a great product to use. Protects well and still has a lot of shine.
-Dan