Thank you all! I scubadived and mounted the new Bowthrusterpropeller, delrinhub and new nylon screws..... I usel mmM8. Stainless steelsqrews as Kevin pointers out. 30 minutes in Water and preparing sqrews took 1 hour. I Sidney have the tight length . But I trimmed and modifyed what I had. The propeller sits tight with is importstopp..