I'm currently working on reducing the weight of the spacer plate, but right now without the gearbox and wheels the entire assembly weighs in at about 36 pounds according to Inventor.
Edit: About 1/3 of the way through cutting out unnecessary material the weight dropped down 2 lbs in total on the final assembly.
Edit #2: Finished reducing the weight of the spacer plate, managed to bring the full assembly weight down to about 30 pounds.
I had to render it in Inventor Studio with the Illustration shading to make it easier to see, but this is what the spacer plate looks like now, rather than a solid plate like it was before:
