Do a search on the oa. You will find a lot of information on hitches and 1 wheel trailers.
As far as connecting to the swing arm per axle/axle hub I am not so sure I would go that route. The final is connected to the swing arm, this would add stress on the 4 final bolts as well as he swing arm bushings. The bushings are made of rubber. You might be just fine but then you could end up with some serious problems at the wrong time.
Home made trailer hitch here:
http://www.vtxoa.com/forums/showthread.php?t=294763&highlight=1800+trailer+hitch
As far as connecting to the swing arm per axle/axle hub I am not so sure I would go that route. The final is connected to the swing arm, this would add stress on the 4 final bolts as well as he swing arm bushings. The bushings are made of rubber. You might be just fine but then you could end up with some serious problems at the wrong time.
Home made trailer hitch here:
http://www.vtxoa.com/forums/showthread.php?t=294763&highlight=1800+trailer+hitch