Baseplate should be parallel to the wheel otherwise wheels will mesh on angle and will cause negative effects.

Add brass washer to axle before mounting wheel hub.

Attach wheel hub to the hanger and lower down motor to prepare gear meshing.

Motor gear and Wheel gear should be always parallel to each in all wheel position. If gears not parallel and at angle it can cause negative effects and product more noise than necessary.

Loosen up motor bolts so that motor gear would press wheel gear.

Use sheet of paper to drive it through wheel gear and motor gear. Spin wheel to push paper through the gears

After meshing is good tighten motor bolts