Hi Bluemonster , I have some insight on production numbers for your 71 challenger R/T options.
Let me start off by saying that it was very much possible to get left over production peices like your console ,although My challenger r/t with a vin of js23h1b163xxx had the correct ashtray at the rear of it.
here,s some info for you on your cassette option.
These numbers are for 1971 challenger R/T s only...
7.9 % came with the AM radio with cassette player
4.4 % came with the AM/FM with cassette player
3.7 % came with the microphone ( for the cassette player/recorder ) ( separate option and price )
There you go ,hope this helps answer your questions.
take care 426