On the pre 2014 model it was difficult with engine in frame, but just possible. On the 2014 onwards IRS, dead easy once you removed the back end of the bike. I came to do it on a late swinging arm model yesterday and it wouldn't come past the rear frame crossmember. I had a feeling I had done the job before with no problems, then twigged, the first time the rear output shaft bearing had stayed on the shaft, this time it was in the case. I pried out the rear oil seal, knocked the bearing forwards out of the case, which was already pulled back as far as it would go, and got enough room to wiggle the case past the crossmember with ease. Reason for removal, was a faulty trigger coil, they do seem prone to failure, and always the type with wires from the top, Mitsubishi trigger coils don't seem to fail.