Anyone know of rear fender flares in the 20mm offset range for g37 coupe?

So i’ve been trying to fit a square 18.5x10.5+15 wheel setup with 275/40 tires to follow along with the 370z track cars. I cannot get the rear to fit, even at -2.5deg of camber. I would like to be at -1.9deg to compliment my tire setup and car purpose. I’ve already had my front fenders rolled by mrsexys2k, but he said he can’t do anything about my rears besides trimming the liner.

So i guess the only option here is to cut and fender flare the rear. Does anyone know of a subtle rear fender flare for the g37 coupe? All i see is those universal plastic duraflex flares but they look horrible honestly. Its not a show car, but i don’t want to look disgusting either. Liberty walk is way too wide (75mm flare). I only need something like 20mm-ish. I’m attaching pics of the wheels when they were at -1.5deg of camber (closer to my -1.9 target).