I've done a few minor things with the interior of the car so far.  A few years ago, I purchased a set of European-spec "white" gauge faces to replace the factory black faces.  Looks almost identical to the S2, and still illuminates red at night.

I've also finally replaced the aging drivers seat with a nice used Recaro, not sure what model.  It has adjustable torso bolstering, adjustable thigh support, and still flips-forward for access to the rear seat.  The only caveat was that no one makes a base for the power seats found in the CQ.  No biggie, I made an adapter to go between the factory electric base and the Recaro seat.  Materials all came from Lowe's, and I used our TIG welder and Purdue's Student Machine Shop in the Mech. Eng. building to cut and drill all the bolt holes.

I've also added a Clarion 6-cd changer in the drivers side under-dash parcel tray, Blaupunkt 3.5" 2-way speakers in the dash, Kicker Comp 8" sub in the hatch, a Coustic 35 watt 2 channel amp bridged for at least 100w RMS to power the Comp, and a Blaupunkt Aspen tape deck.  Factory rear speakers have been bypassed.

OK, so the Coupe no longer has a stereo, as I removed it for use in the '87 5000q. That includes the amplifier, subwoofer, CD changer, speakers, and the Aspen.