I agree with Ken. You could put the right rear on the back wall about where the "28'" label is (or above the window if there is enough space),and the left one on the back wall, a few inches from the side wall.

The only other alternative I can come up with is to suspend them from the ceiling with Axiom's Full Metal Bracket, or Omnimounts.

Jack

"People generally quarrel because they cannot argue." - G. K. Chesterton