It's been a while since I swapped mine out as part of the 21" upgrade kit but I remember it being difficult. As I recall the instructions say to remove the swing arm. What I remember doing was having someone forcibly spread the frame and the swing arm by putting their feet on the swing arm and pulling up somewhere down low by the fender. It gave just enough room to get it out.
2013 XC Suede Nuclear Sunset
21" Conversion incl. ABS Module, Rear Shock and Forks
Lloydz HPT Cams
Lloydz Air Filter
Lloydz Timing Gear +4
31 Tooth Drive Pulley
Southern Motorworx Tune: 118.08 HP - 114.97 Torque (before 31 tooth drive pulley)