It's really cool

Unlike your rear axle, I'm not satisfied with this one... The bearing sizes you listed don't exist, you need 3x [8x16x5] inside diff + pinion gear/shaft and 4x [9x17x5] for the axle+steering arm. This print requires 2x [9x16x5] for the diff to fit in the diff cover, but it's a non existing size. Going to replace it with 2x [9x17x5] or [8x16x5] whatever fits best, drilling/filing required. Axle gear lhs/rhs dont' fit inside UJ inner lhs/rhs, the diameter is more than 1mm too thick. I'm starting to believe the files aren't the same as the ones you used yourself to make the assembling video. If you fix the diff cover (part 1+2) to be able to fit the [9x17x5] bearing and adjust the diameters of axle gear / UJ inner, this print fits in perfect with your rear axle.