MaxMAtt;
You seem pretty setup but I thought I'd share how I mounted my PIAA driving lights on the opening on my IMPUL aftermarket bumper.
THe local home building supply company has metal strips that are used in lumber construction to re-enforce to pieces of lumber coming together. about 8 inches long.
They bend with a vice gripe pliers.
I then bought some AMG side grilles from a 2004 C230 (or 320) and did a little custom work to make the grill fit.