Gregor,
I'm fitting handguards at some point, either Acerbis or the simpler Yamaha shield type. I've seen a few examples on the big Tenere thread on advrider. Another definite fitment at some point will be heated grips, Andrew and me both had them on our trade-in bikes (for the Teneres) and both miss them. I ride quite often to Aberdeen, leave my bike at NCP longstay at the airport (free for bikes) and go off to work for two weeks. 200 miles is a long way with cold hands.
Anyhow, back to the main point. In the Murray bike museum on IOM, now sadly closed, was an exhibit that might interest you. The prof, Harry Lundberger donated his bike, complete with topbox: