After watching a few videos on the difficulty of replacing stock pole spring i was hesitant to try it. I installed a blowsion on a 2013 superjet.
It took maybe 15 minutes. Didn't have to cut the spring or bend it. Granted i had two people helping me line things up. Would have been very tricky alone but with help no problem. Not sure if different years are more difficult. Basically remove nut, unbolt the bolt (not all the way, enough to to remove spring) replace spring, reinstall bolt had to tap a few times with rubber mallet. make sure bolt lines up so you aren't cross threaded. replace nut. good luck
It took maybe 15 minutes. Didn't have to cut the spring or bend it. Granted i had two people helping me line things up. Would have been very tricky alone but with help no problem. Not sure if different years are more difficult. Basically remove nut, unbolt the bolt (not all the way, enough to to remove spring) replace spring, reinstall bolt had to tap a few times with rubber mallet. make sure bolt lines up so you aren't cross threaded. replace nut. good luck