Just a little piece of info.. If you can't build the swingarm, you are going to have a heck of a time with everything else.
The swingarm should be the easiest part, especially if you're just using round or rectangle tube.
How will you make bends for the sub-frame?
Gussett pieces will be harder to make than the swingarm.
I just want you to think about this before you get in over your head.