Neither are specific to the V. You basically give them the measurements for the supports and overall width (in my case determined by CCR).
For all carbon fiber budget around 1500-2k
D3's are one offs made out of sheet metal that serve to cool brakes and their oil cooler IIRC.
For Grand-Am, Powell removed the whole assembly and added tubing just for the brakes. They simply zip tied it to the mesh. Yooper had something similar I think
The old T2 cars had the assembly cut in half removing the fog light portion, again with tubing for the brakes.
My setup just uses the stock openings with carbon fiber mated up.
I think the biggest issue that will come up is that the ECU is mounted on the leftside just above the assembly and that poses the most issues for clearance with the ducting and any ram-air intake setups. Of course anything is possible with enough money but it may get cost prohibitive for some, especially losing the fog/turning signal in the process.