Given the benefits of having an octagonal chassis (covered in other threads), I've been working on trying to incorporate this general shape while keeping our same WCD-style construction methods of 1x2 tubing and gussets. Below are two preliminary concepts.
In the first two pictures, the "traditional" method of running chains between the gearbox and rails is used. Because the outer wheels are now on the inside of the frame, this pushes them further from the 1x2 tube and I'm a bit worried about the loads on those axles.
In the second two pictures, the chains are run inside the tubes using the 221 Robotics double sprocket method. This helps keep the outer wheels close to the tube, but is a solution we've never used before.
These are still preliminary concepts so the models aren't perfect and are missing some pieces, but just intended to get the point across. Please ask questions and submit comments, as I'm hoping to incorporate some peer review feedback in the next iteration of the design.
Not gonna lie, I wanna marry the person over at #254 who does their wiring... I have admired it for years. :) - Lightfoot26 [more] 
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