Over the last 15 years I have tried a couple different ways to improve the seating position for the taller guys like myself. At the same time I did not want to reduce the streeability of the seats.
The factory seats dip down between the rails, and you would be hard pressed to lower them an inch without removing carpet, and you would need to go fixed mounting for a result anywhere near 1 inch. you also may need to remove padding from the carpet material. What I found was the problem with the factory seats is that they V up on the bolsters a great deal, keeping anyone with larger than a 30" waist from sitting as low as possible in them. My thighs in particular would get undue pressure, and make my R foot fall asleep with the factory R1 seats.
I did get about 1 to 1.5 inches when I got some sparco torino 2 knockoff seats from eBay years ago. I adapted them to the factory rails with steel plates, and they served me well for 5 years in the FD and I still use them today in my van.
BEST solution - you don't want to know.
but you decided to read anyway... The factory RZ seats are amazing. guys with a 34-38" waist fit VERY well, and they drop the factory seating position about 2 inches with the factory rails. They do this by minimizing the seat shell, and therefore making more space where the factory seats have plastic framework.
problem is they cost a mint for a used seat, and it is tougher to get the factory rails (ask lane change).
Ronin has considered making them since Recaro has stated they will not, but that sort of a project brings huge costs, and liability as considerations.
