It's easy to forget how relatively new sun/moonroof technology is -and how relatively old our SVXs are: 1989 was early in sunroof history. I owned a couple of early sunroof models. In 1990, I purchased a 1984 Kalahari Porsche 944 that had a removable panel. I had a nice brown leather (or vinyl) bag to store the panel in the hatch area. In 1991 or 2, I got a 1988 2nd-generation White RX-7 Turbo II (188 bhp!, as I recall). I believe that RX-7 was the first car with a factory power roof. I especially remember that at 6'1" -and a full heard of hair, I barely fit in that great car, but that the sunroof area allowed me to tilt my head slightly to the right to get a better fit. Note that those early designs were for the tilt tops like our SVXs, and internal ones (which tended to steal internal space) came still later. Prior to that period, sunroofs -at least, in the US- were all sourced out after market.
Moreover, designers tend to be purists and most or many consider sunroofs as crass production/marketing matters; so many early concepts are "purer" artist editions. My brother was a purchasing manager for a manufacturer for many years and he still considers sun/moonroofs as tacky afterthoughts.
