I seem to remember a post (on moparts) regarding the tail light area and black-out.
for the most part all R/Ts got by color as stated above.
but somewhere along the way (i think at hamtramk plant) there was a directive to paint that area with blackout (long as not a SE)
it happened for a while then it was stopped. I think it was towards the end run of the 70 model year.
I very clearly remember seeing this blackout applied on a very/very low milage original 440 RT. the car was red/red with a horizontal body stripe (not bubble-bee one).
Not an expert here - just something I recall.
Bill
Don't remember that at all, I don't believe any regular R/T's received the blackout, just those with the added trim panel... And of course all T/A's.... But not that it matters there are plenty of Challengers like my R/T vert with the blackout added as a matter of owners preference... Or in other words... It looks good blacked out....