RE Intake noise: This is addressed fairly simply. CB turbo hats and 2" cone filters on the end of each hat. I had to get shorter velocity stacks as well. $130 for aluminum turbo hats, $10 for gaskets, and $25 for new 2" cone filters. I think I paid $20 for shorter velocity stacks.
Reduced my full throttle top-up decibel level from 107dB to 95dB on a Spyder. Part throttle cruise noise was also reduced. Game-changer for top-up with NO discernible performance change. The car went from deafening to tolerable(with noise-reduction earplugs). I would expect similar in a coupe if it turns out to be too loud.
Initially I added an after-muffler then realized it was intake not exhaust that was killing me.