The seatbelt light bezel wasn't on the dash pad, it is on the dash frame between the ash tray and glovebox. The only differences in dash pads in 1970 was color, 3 speaker or single speaker, and AC vs non AC. The Challenger script was always there regardless.
I've seen a lot of '70s with ash trays in the console too, the fact they are in restored cars today doesn't mean any were built that way in '70 either.