Folks are experience the same 'height' issue with the top of the Leo Vince can making contact with the Happy Trails rack. I'm not, but it is an issue for some.
Most aftermarket exhausts for this bike sit 'higher' when mounted than the stock can. The Wolfman rack is designed around the stock exhaust. Seems it's a problem with the rack not being designed around aftermarket cans. Another inmate (not sure who) had this same issue. He called Wolfman and they made him a new rack that allowed for the aftermarket Leo Vince can. I'd keep the exhaust since it's not the exhaust that is the culprit. The problem is the rack, being it is designed for the stock exhaust.