headers are so easy on a 5th gen. I am a private guy but will install near Richmond VA. Tune is up to you. I have installed a few sets so far and they fit great. What brand? I will put them on for half what you were quoted.
'15 Z/28 #325 black a/c & stereo. 2:11 VIR Full 1:45.531 Summit Point Shenandoah Circuit
Advanced Induction cylinder heads & B-3 cam by Race Proven Motorsports. 575rwhp/500rwtq
'12 ZL1 10.52@131 1.55 60' 2:13 VIR Full (sold)