Yamaha Lower Unit Assembly - 6GS-45300-26-8D. Restore Factory Performance with a Genuine Yamaha Lower Unit. The Yamaha Lower Unit Assembly - 6GS-45300-26-8D is a complete OEM replacement designed to restore your outboard's power, reliability, and efficiency. Built with factory-installed internal components-including the drive shaft, propeller shaft, bearings, and seals-this unit delivers Yamaha-grade precision and durability straight out of the box. Whether for recreational boating or profession