More photos of the #Xtrac 295. It uses a double drop gear arrangement which allows 4x final ratios for any two sets. The plated diff only came with a 60/60 ramp config but should be a good starting point. Currently I use a 60/40 but have used a 70/30 as well. If you look closely, the crown wheel bearing is larger diameter than the actual crown wheel. The reverse arrangement is a work of art by itself.