I have found that, with a halo seat, it needs to be mounted as low as possible and as far back as possible. I attached extensions to the pedals so I could reach them with the seat low and back. By doing that, I felt much more comfortable and can exit the car with helmet and Hans on. Of course, it took 3 times to get the seat to where it needed to be to be able to exit the car. My extensions were not 2" though. You might want to experiment by putting some temporary extensions on the pedals with racer tape to see how if works/feels.
Extending the pedals is not a problem, in my experience. The limit, of course, is being able to reach the shifter when buckled in tight.
Big Dog