1) I found that when working on chassis/cages ext. it's easier to use a wire welder to tack it all together and then braze it after. It's nice to hold the piece how you want it with one hand, close your eyes and then a quick squeeze with the trigger.
2) ran across how to make a great tube bender on the RCC Tool section:
Some washers and a spacer the size of the tube you are
3) for the few still running twin force axles. the dremel thin cutting wheels are the same size as the axle tube. great for making link mounts or what ever you need that will be mounted to the tubes.