Finally got around to installing my late 1980's Prelude seats in my late '74 260Z (has the hump in trans tunnel for cat converter). I actually only installed the driver's seat....have not installed the passenger seat because I need that space for my race wheels!
The install probably took a half day. I had to cut, bend, and basically destroy the stock Prelude sliders in order to make them mate with the stock Z sliders (via heavy gauge flat bar and angle iron). Also had to "massage" the trans tunnel hump slightly to get sufficient fore and aft slider movement.
Very happy with the finished product. Although they're over 20 years old, the seat is extremely comfortable and supportive. You can see from the pictures that it has adjustable lumbar support, adjustable side bolster support, "fine" recline tuning, and a recline "Memory" function. These seats are also very light, and they look great. If you're using a 4- or 5-point harness, the shoulder straps thread easily through the headrest posts.
Hope this info helps, and happy motoring to all!