[NickE]

To save a bit of weight, you could probably go with smaller sprockets.
Are you using 25 or 35 chain?

Also, what is the material for the gearbox sideplates?
254 typically uses Delrin, as it is much lighter than aluminum and strong enough for this application

Finally, when looking at your picture, there are grooves cut out in the front of the side tubing.
Am i correct in thinking that you will be putting another black crossbar in the front?