Depends on how the BG is packed.. there is no sure fire way of shipping a glass, it is always a risk. The risk though can be lessened with good packaging and choice of courier.
I have a timber box I make to ship glasses in.. DDstoys has it at the moment and maybe he can supply a pic.
But basically I get the 40mm X 16mm pine short cuts from Bunning ( $1ea or so) and use them to make a timber frame 40mm depth that is some 30mm or so wider then a backglass. This is then faced with 4 or 6mm MDF.
Stand on end and attach a handle to the top to make it easier to carry ( this is essential or it will one day be dropped by the numpty courier). Make sure the box is labelled " FRAGILE GLASS"  in big bold letters with arrows facing upwards ( never assume the courier will work this out themselves).
I normally cut polystyrene corners from some old packaging and keep... these fit on the corners of the glass and keep it in place in the box.. shredded paper and you should be kicking goals.
Main point to remember is that if the box gets dropped then the shock will travel through anything inside killing your glass so don't have it tight in there.. you need a bit of movement as this will lessen the shock to the glass and hopefully keep it intact.
You send this box to WA and have the glass put inside and sent back.. courier both ways.
Good luck!