You can purchase flexible chrome wheel arch molding at your local auto parts store (Pep Boys here). I believe it's 1/2" - maybe 3/8" (check). Fits perfectly in those grooves - trim to fit. I think it was about $15.00 or so for a roll.have you seen the chrome that fits in the groove on the bumper?
This is really a personal choice.
Do a quick google search to see what your state laws are regarding what the legal limit for NC is. Otherwise you risk the chance of getting pulled over and ticketed for illegal tint? I went with the darkest legal tint for rear and just a tad lighter for front....reason being because even during night driving with the legal tint....it is VERY difficult to see outside.
Any good local tint shop will be able to show you the variouos shades prior to you making the plunge...good luck.