I cannot understand the above posts.
I have pulled these things apart and I can assure you that my 2002 D2 has a seat that is integral with the base, and you cannot move the rails at all.
The base is also assymetric and AFAIR , would be very difficult to relocate as the mount nearest the tunnel is vertical on the front of the floor bulge.
When I fitted Recaros to mine I had to cut the seat from the base and weld rail mounts on to the rails. I was able to then give the driver's seat more travel but not a job to approach lightly.
Regards Philip A

