I had noticed Nathan's (Boxerworks) G/S at the Georgia Mountain Rally last year and asked him about the upside down lever on his bike. He said it was easy to do, take a grinder and match the cam profile to the back side of the ears. So the seed was planted......
Before picture stock setup
Stock brake location
Remove brake cam and make a cardboard tracing of the original
Cut out cardboard and flip it over like so...
Spray paint to get new profile
Here's the profile.
Start cutting w/ and angle grinder and cutoff wheel. Here's the 1st cut. Hopefully before cutting I don't have to tell you to remove the two o-rings...do I??
...And more. Proceed slowly and hold the grinder flat.
Keep grinding till it looks something like this, this still needs a little work
I was probably paranoid about weakening the cam as there wasn't as much material on the back side. See drawing.
So I added metal w/ the MIG welder then smoothed down the welds.
I then smoothed out the cam where the brakes will sit with a 120 grit sanding pad on a pneumatic angle grinder
Then inserted the cam in the final drive, you will have to flip the brake shoes over and relocate the springs to the opposite side.
I did notice that the springs may touch the OUTER edge of the FD seal. If this was on the inside edge I would be concerned. The reason for this is that the back bone of the brake shoes favors one side. A little hard for me to put into words but you'll see what I mean.
Put the wheel on, not necessary to bolt it in place, you will have to adjust the brake arm to get it in the correct location. You'll have to fiddle with the arm to position it correctly. Bolt the wheel on then adjust the brakes. Ride the bike a bit to make sure the arm doesn't need to be moved. Once you get it in the right location mark the lever location on the cam with a center puinch.