I ran across this web site for aluminum rear backlight louvers. These are not the cheap ABS variety, but are patterned after the 1970 (A44 option) original, with hood pins and hinges. They either bolt on or can be secured by 3M tape. They are expensive at $1,200, but you get what you pay for.
What you you guys think of this look? I loved them on my 71 'Cuda but am not sure about them on my SRT.
Limited Parts Industries - Challenger 2009 Louver