This one didn't fit, didn't function, but.... - Radian Weapons Talon Ambidextrous Safety Selector 2-Lever KIT

I start by saying others have gotten excellent results. I have two identical ARs. I bought a "Radian Weapons Talon Ambidextrous 45/90 Competition Safety Selector 2-Lever KIT R0233, Red" for my wife's AR, and it was PEREFECT. So much so that I wanted one for myself, but in black. It stuck out the right side so far that at first it wouldn't function. By moving back and forth, I found the sweet spot and it would function, but then it stuck out so far on the right side I was able to slide a small allen wrench between the upper and the base of the selector. I could have gotten a washer, but that's not what I expect from a quality add-on. I returned this one and re-ordered the one in red. What's the difference between the red and the black one???? The red one fit perfectly, the black one didn't. I appreciate many others have had excellent results, but I didn't. I still recommend it, but With Caution.