Perhaps I shouldn't say anything because I don't have all of the detail here at hand. But, I would caution that the "width" of the center core of the Valkyrie rear wheel may measure less than that of the GW wheel. In an earlier post (
http://www.valkyrieforum.com/bbs/index.php/topic,96291.msg955977.html#msg955977) I described machining a set of tapers (cones) for my local dealer's service department. The tapers they used on their Snap-On tire balancing machine could be made to work with a GW rear wheel but were too long to seat properly in my Valkyrie wheel.
I was intent on machining tapers to fit my rear wheel so I did not spend time measuring the hub of the GW wheel. My experience machining the tapers causes me to believe the center core of the GW rear wheel is thicker.
I have no idea how that might affect left <-> right alignment of the Valkyrie wheel on the GW swingarm, but my initial impression is that there may be a problem.
Good luck to the other poster! I hope he is able to get things to work well and safely.
EDIT: I agree with Robert - adjusting the suspension is likely the better thing to do if the issue is seat height. But, I am concerned that the shock link (which lowers the ride height and, thus, seat height) greatly reduces the GVWR of the scooter. Suggest to the OP that he check how the shock link changes GVWR; if the intent is to ride two-up it may be an issue.
Cheers!
Bill