$30 later, I found a spare swingarm to use as the guinea pig:
This thing cost as much to ship to me,
as it did for the actual swingarm.
I've since dropped it off to Rob last week to get to hammering, and yesterday he sent me the first pictures of the swingarm in its mock-up stage:
For the mock-up, Rob used an oil tube cut out to create the fill-in pieces on the swingarm for reference with the aluminum pieces he's eventually going to use. Before we got started, we were mort wary of the chain side of the swingarm, as the upper brace is not flushed with the lower arm. This mock-up seems to be very promising considering our concerns:
Oh, it's getting pretty exciting right now...