you can't push it any more towards the deck?
I don't know. it's seriously not something I've ever looked into. for one thing mine don't have sides that stick out and the other I haven't looked into it is because having only an inch on each side when loading a mower is not a big deal to me.
be sure to stop over to the wax your mower thread with that pic cause it looks like you at least wash your mower.