1971-1973 Arctic Cat Snowmobiles Factory Service Manual, Page 121Get this manual
TRANSMISSION (STLAWRENCE) 6Compress the synchronizer toward the drive plate and remove the retainer bracketCarefully allow the synchronizer to retract away from the drive plateCAUTION: The coil spring contained within synchronizer is very strong and will force the synchronizer away from the drive plate if pressure is not exerted against the spring tensionSlide the spring collar and idler bearing off the drive plate shaft