My wife actually came up with a brainwave this morning! We have just re-done our backyard and I have raised the garden beds about 0.5m via a brick retaining wall. They are completely empty at the moment and full of organic goodness just waiting for me to plonk something in there.
The wife suggested we dig up our Little Gems from the front garden and transplant them in the back. Not a bad idea I though!
Although the back does face west, it does get some shelter as they up against a north west facing wall so the area does get some shade. The spce that needs to be filled at the back is pretty identical the space the Magnolia's currently occupy in the front yard.
The Little Gems are about 2-2.5m tall - does they cope well being transplanted?
I was then thinking of putting in some Murrayas at the front of the house - maybe they would cope a bit better with the heat and the front fence?