I have TFX Pros on my Walther PPS and HK P30v1. I love the sights, but I want to tone down the brightness of the rear fiber optics, without completely/permanently blacking them out. I am considering black, blue, or red Sharpie, either on the top light-gathering area of the sight or on the rear-facing dot. Another consideration is cutting a small section of black electrical tape and covering the top light-gathering area. What is the best option for dimming the TFX Pros that is not complete and/or permanent?