I have a set of excellent ally panniers, made for, and used on the GS for our trip across Argentina. (you can see the bike, panniers, me and bits of the Andes in the last 3 photos here including the bike on it's side
They were too much for the XR, but would suit my TA600 and my plans for it! But how to mount them?
The panniers have four mount points each:
One front, bottom normally braced at the pillion footpeg bracket.
The other 3 are used to secure the bin to a mounting frame: one bolt at the front, top and 2 more vertically down the back edge, top and bottom.
I am thinking the same for the front bottom, and somehow welding a plate for the front top to the sub-frame (buy and cut some used side panels for the plates to feed through?).
The rear two points I was thinking of using piece of steel flat bar, across the top of the rack, with an arm weled at each end to run parallel to the pannier bodies, drilled to match the mounting holes on the bin. Add a diagonal brace between the two vertical arm sections and voila.
It (the rack) would need to partially support the bins, and even a top box, although I would be packing only for one, possibly two on short trips, so it would not be tons...
Question is though is the rack strong enough? Are there any other flaws in this plan?
Adventure: it's an experience, not a style!
(so ride what you like, but ride it somewhere new!)