Detailing non-engine area of engine bay
 

I've used soap and water, Windex and degreaser, and have gotten my engine and chrome areas looking pretty good.

My problem is the other areas of the bay -- the wheel wells, the back wall of the bay, the frame areas and underneath the hood. I can't seem to get them clean. They still look dull and almost stained from dirt/grime. Painting the areas would be nice, but not an option right now.

Is there something like tire dressing that can be applied to these areas to liven them up for when I'm at shows? Thanks.

I spray purple power all over it and let it sit then hit it with the powerwasher as for a shine I spray turtle wax spray detailer and rub it in with a rag