Lots of wobbly information on the Yahoo Group site, probably now in the files. One of the inmates over there ("Jon") recommends a slightly different aspect rear tire, which raises the rear. I did the same by dropping the triple trees on the front fork by about 3/4".
Check the steering head bearings. If they're even the slightest bit loose, or out of grease, they could be part of the problem.
Fork brace might help, though it isn't intended to solve wobble, but fork deflection and twisting.
Steering damper might help, but the bike wasn't designed to wobble--I'd look at the steering head bearings first, or perhaps a blown fork seal that's let one of the forks lose some of it's oil. (That would cause a difference between the damping on each fork . . . . )