I need to mount a ceiling mount handicap lift in my motorhome.  The weight must be born by the sidewalls.  I would like to use 2"x2"x .125 thick aluminum tubing from wall to wall to mount the track for the lift.  The span is approx. 96" and the weight point would be slightly off center.  I am not capable of figuring the load ability of this tubing and would appreciate some help.  If this tubing isn't strong enough how big would I have to go?  I don't want to use steel if I can help it because of the added weight.

Thanks,

Roger