ok, I made a bracket like Steven's tonight, using some strapping I found at home depot, its very thin metal and has some small and large holes. the large hole works without a washer to be held on by screw that holds the rack rests on the WSM.
After I got it on there, quite proud of myself, I decided to cover up the WSM since a storm was rolling in. Well, I discovered the fatal flaw with this bracket, it sticks way out and the cover doesn't go on easily!
I'm planning an improvement though. I haven't found it yet, but I want to get a hinge, that is tight enough it could support the weight of the transmitter and a bit of wood, but would allow me to fold the entire contraption flat to put the cover on the WSM. I'll post pics if I find the hinge and get it attached.