Recommend prop for a 2017 evinrude g1 150h.o. on a ranger 198p

[ClaytonHaske]

Looking for recommendations on what size prop I should be running in my 2017 ranger rt198p. It came with a 15 x 21p rebel ss prop, but, I don't think it's the correct prop for this boat. I honestly do t know what my rpms at wot are? I'm gonna take it out today and test it out. Everyone I talk to has a 23p prop on their 150hp rt 198p's. I'll report back what my wot rpm range is. The motor should be running at 5850 at wot, so we'll see what it says today.

[ClaytonHaske]

I was getting 54mph at 5200 rpm, with a passenger, light load, and 3/4 tank of gas.....I know the motor should be getting more rpm's, but it's only pushing a 21px15" prop. So, I know the prop isn't too big. Anyone have any recommendations? Thanks for your time.