Well after much looking around, i found a top Box Luggage Rack for my Bestem TopBox that is fitted to my ST1100, which i bought from Revzilla,
http://www.revzilla.com/motorcycle/givi-e96-luggage-rack Cost me $147.00 Australian landed to home. It is a very robust item and well worth the money
It is a very simple install yourself, just need to take the time to make sure everything lines up.
I used a non-permanent blue marker and placed the Rack on top of the top box and lined up where it best sat, circled the bases, double checking myself of course
I used a drill bit slightly bigger than the Bolts, so there was a little bit of play if i was out at all, i added larger washers on the inside to just add a little extra strength to it all.
I have put this on not to carry more gear, but to be able to carry different items, and to tie helmets to that sort of thing, and when i have Teela with me, it means that we can put our mini camping chairs on board to.
Before
After
Side View
Underneath the lid
The full bike view