ok good info. So yes...I took my beds completely off ( I used pins to lock bed arms then at same height), square shaft that drives opposite wall is disconnected, carriage bolts are off. so with this done I have a tiny bit of play on the top horizontal motor bar. Question...I notice that under the wall mounts verticals are a bolt and nut. Does this nut adjust the chain tension? If so would it be ok to lesson the tension to help get the chain off the gear?