I found a 1984 Cadillac Sedan de Ville with a primo back seat in just the shade of blue to match my T. So I bought the bottom and the seat back for a song. The bottom is kind of pillowed like the Limited, with much more padding than the stock Regal. It fit fine with no modification. The seat back has the center fold down arm rest. But it did not fit so well. It was about 4" too wide, so I had to partially disassemble the upholstery to shrink each side by 2". It was a PITA, but it's easy to forget now that it's in. I'm very happy with it.
Red Regal T must be too modest to mention it, BUT he has put in the most thoroughly bitchinest interior imaginable. In black, too. If the link above works, it will show you his handiwork. Be sure to click 'next' or 'previous' to see them all. If the link I pasted doesn't work, search on this board for the thread in Junkyard Dogs for this.