See details on my blog at www.hnagib.comThe steering module at the back can be directly glued on to the rear end. Another way to attach it would be to glue on the two "Assem1 - Assem_steer-1 steer6-1" parts to the "Assem1 - Assem_steer-1 steer1-1" part as shown in the assembly image. This way the steering module can be attached by simply sliding it on. The steering module fits a mini servo perfectly. It was built to fit 'TowerPro SG90 9G Mini Servo' model. The boat can also be skid steered if you can control the DC motors independently. "Assem1 - Body_back_end-1" should be printed with the pump outlets facing up. The holes for motor shafts have been extended to convenience of printing. The can be easily broken off after. I found a rubber tube to work best a shaft coupler.