I took one apart a few years ago, are you planning to use an electric knife?
The seat element took a bit of getting apart as it was glued to the thin foam covering, which didn't survive. The element can be removed and then the seat trimmed, and then a covering re-applied.
Having purchased foam and glue myself for an earlier project, I wish I'd just got that one done by Tony as to be honest, the wasn't much in it.
My 2104 has been retriimmd by him and it's very comfy, he even reprofiled the seat for me.