You guys are the experts - but let me offer a small bit of advice,

I've used a WB for two years now. The times I had troble with left/right, I found that my plastic fletchings were hitting the bottom of the rest, or in your case it could be the riser as well. I turned the nocks a little, and the problem went away. I use an adjustable crosshair sight, one other time I found the when shooting at past 40 yds (for practice only) my fletchings were kissing the ring of the sight.

I ended up going to a little smaller fletching in the end, the 4" ones I had in the beginning were a little harder to get to clear the riser, or the base of the WB.

Hope you get it figured out.