Hi, just a few things to perhaps help you make the skin even better:
Consider cage-transforming the roof logo to follow the curvature of the roof edge. Also, shrink the high performance brakes logo, it's small on the original M6. And with the bumper, tricky, but the Kunos M3 GT2 template requires the logos on the bumper sides to be scrunched down front to back. That way, they appear the correct size on the 3d model. Good job!