On my -6A...
...I used Van's foam kit. I am 6'2", and 250 lbs. My seat foam is 1.0" thick, seat back positioned in the aft-most position, and my seat foam extends 1" in front of the spar. My head and headset just clears the canopy and sun shade.
Passenger side seat foam is several inches thick, and the thigh support is flush with the front side of the spar.
