My motor is a 1998 115hp Mercury 115elpto. The prop number that's currently on it is 48-16988-18. Right now the issue I have is I'm over reving I can get over 6000 rpms with this prop and I do believe max rpm is 5250 I think. So what I gather is I should go higher pitch 19 or maybe 20. But what I need to know is what style hub, prop diameter and shaft diameter do I need. Any help would be greatly appreciated all this prop research is overwhelming.