The grill itself is a metal wire mesh with a plastic frame. The box comes from hogtunes, you can see pics here: Road Glide Special
I would call the finish more of a satin than a gloss and think it would look fine with the matte black inner and also looks good on the gloss black they have pictures of. You can get them with a black or chrome frame.
I've never seen anything saying that their systems won't work with the 4.3 and when I ordered mine I don't remember them asking what kind I had. Can always be safe and give them a call.
Freedom isn't free, remember to thank a vet.
2018 CVO RG lava orange, 117 Stage 3, 14" F47 and a few chrome extras. Boom crap gone.
2016 RG Special Cosmic Blue, 120ST with Dragos 2:1 and TTS tuner, FBI drop seat kit and JNR air ride. Stock audio long gone.