I've been perplexed as to how to avoid getting car wax on the black Shaker stripes of my 15 R/T Plus. It is real obvious since the car is jet black also. So after 7 years of trial and error, I finally tried something out of the blue. Today I decided to try using a microfiber cloth that was misted (2-3 spritzes) with WD-40. I tried it in a inconspicuous place first. It seemed to do okay, so I took the leap and did the whole decal. It turned out great and appears to have rejuvenated the stripes plus cleaned off the overage of wax. See the photo attached, the top of photo was wiped with WD-40 . I then proceeded to use it on the plastic air dam parts etc. Only time will tell me if this was a good idea. Any thoughts on this would be appreciated.
I've used WD40 to get old dried on wax off of the hard black plastic on cars. The amount of crude that comes off is unbelievable. The sheen from the WD40 does wear off but the plastic still looks 100% better than before. McKee's 37 makes a ceramic coating for matte black, you may want to check it out for future use. When I needed to strip off old wax on semi or matte black surfaces I used dish soap, it'll strip the was right off. Just know you need to rewax any areas that the soapy water runs over.
The Solvents in WD40 are not good for Adhesives , Meguiars, Chemical Brothers, Adam's all have more fitting and safer products for preserving them.
"I've been perplexed as to how to avoid getting car wax on the black Shaker stripes..." This sounds like you are asking regarding regular waxing, not detail waxing. If this is regular waxing, you can apply BLUE PAINTERS TAPE to the stripe edges and that should keep out the wax. If you are waxing with detail wax spray, such as Meguiar's Ultimate I would be surprised your stripes are affected.