OK, if you are used to a centered rear strap, I think your Kode can be set up that way.
Was your F2 also an "A" box fin (so you could adjust it forwards and backwards in the box?
I would use the rear strap positions and place the front edge of the fin right under the back of the '
As far as differences in sailing style/stance, I think you will probably adjust to the Kode very quickly.
If you have some of fins from your F2 and they fit in the Kode, try some fins that yoiu know worked in
your F2 in the Kode.
Hope this helps,