The plot thickens,
Or your discovering more things that don't fit
Body code is 65A . It has brushed aluminium dash and door trims as mentioned . No roof console.
Am 99% sure the interior is original . Door grilles have lights and square holes for the mounting clips , which makes me think they haven't been added post factory.
So you're saying the trim code should be 6A given the deluxe features ?
Not sure how your determining that the interior is original. Have you compared the date codes on the seat springs, seat upholstery, door panels and the like. Very common for Mustangs in their early years (late 70s- 80's) to be upgraded by their owners using original interiors from donor cars. For 67-8 the clue is that they often didn't add the roof console since whom ever removed the parts typically forgot to grab the brackets that made the installation possible on the other car.
If your thinking that its original just based on the effort it would take to add or modify the car to do something let me offer some experience and suggest that you don't underestimate what an owner will do to get what they wanted. Someone will do almost anything, even illogical, silly or stupid efforts. Have plenty of observations and eye witness stories
Thing your find (using the search feature) threads related to the inclusion of the door grills with the radio option. Might even have swapped doors from a donor car that came with the door grills and or maybe the complete interior
Could the mentioned deluxe features be ordered separately without the complete deluxe items ?
No, the deluxe interior came as a package. Allowing the separate ordering of individual parts in general would defeat the offering of the complete package.