I want to see how your windows look with tint. Please specify what percentage you have when you post a pic. Thanks!
You are correct, you would need to close the sunroof shade and cover the from windshield with brown paper if you use the same % tint as the rear windows to match, you have to go slightly darker like you said for really close match.It is very hard to "match" the front to the backs, since the windshield brings in a lot of light, making the front windows appear to be lighter than the rears. 20% is pretty close, maybe 15% would be a 'perfect' match. Good luck.