Keep in mind that for Inline Motor configurations for axles that are offset from motor shaft (not on same plane) you have to pair the pinions SIPI559o15 and SIPI5510o15 with Crown gears SIGO23 thru 30. The crown gears will be white versus the usual color coding of the other gears. The white/gray motor pods are usually offset due to larger diameter wheels.
Sidewinder pinion and crown gears must also be paired up according to diameter. Be sure to measure old gears before replacing to ensure proper gear mash.