Was searching for rules about FIA inspection of seats and belts ...
when i found out that now they have changed to rules to where your car must have a rear back brace if your bucket seat has sliders.....
but the problem here is, no seat sliders i know of are even FIA approved.
In addition, you can't have a rear back brace, unless you have a rollbar/cage installed.
This forces drivers who have a race car with 2 drivers (and needing to adjust seats) to either put a rollcage/rollbar with a seat back brace secured into it, or have a FIXED bucket seat with no adjusment while having the brackets also FIA approved.
To further the problem, you shouldn't be drilling into your Composite Bucket seats with the rear back brace. There are only 2 companies i know of that has a built in system where you don't need to drill holes into the composite seat.