If you have seen the factory one, you might want to make one as the fit and finish on the outside is fine, but it is unfinished on the underside, along with weakness around the mounting hole. They can easily crack if care is not used to secure them. The two carbon ones we have seen were cracked around the rear mounting hole
One of those was cracked so bad that we remade it using the OEM as our mold and added a reinforcement between the layers where the mounting holes are, along with using a bonded sealing washer when installing. We also used a rhino liner type spray on the underside to protect the exposed, unfinished carbon
Making one is easier than you would think, but it's a little labor-intensive and messy but super fun to turn out a cool part.
Also, note that this was back when the factory was in turmoil and couldn't get any parts before getting heckled for making one! Since November of last year, we have been receiving parts over the last couple of months with no issues.