We are putting a set BMW sport seats (taken from an 84' 320i) in our 72' 240Z. Well ok, it is my husband's 240z but I am in charge of making it look pretty while he makes it go fast.
The previous owner cut out the rusted floorboard and installed a diamondplate floorboard so we are using the original BMW seat rails but cygnusx1 has some photos posted on the site here somewhere on how he modified his BMW seats to fit the original Z seat rails. We weighed them and each seat weighs 42lbs! But still isn't bad for a multi-adjustable seat that is comfortable and sporty. Although the bolsters are pretty stiff and very narrow...I doubt a large framed person would find them suitable.
https://www.dropbox.com/sh/acn5b6te3135hh4/D5xEFmW6Qv?n=80737869#/