New Prop For 21 ft cuddy with Bravo 1 Drive

[mr300z87]

I have just purchased a 1989 Invader v210 cuddy cabin powered by a Mercuiser 5.7 L 260,and a (Unusual for this type of boat) Bravo 2 Drive. The current B2 drive is 2.0 to 1 ratio and has a HUGE 17" x 25 pitch prop on it and apparently hits close to 50 MPH I do not know what WOT RPMs are. My plan is to replace the B2 lower with a Bravo 1 lower and my research tells me that with the B1 lower the ratio will now be 1.5 to 1. My questions is what size and pitch prop is a good starting point? I have an aluminum 14.5 X 19 prop I could try and also a kinda beat up 13.75 x 21 also that I could try also. Not sure if these props are in the right ballpark but I have them on hand. I more interested in a good hole shot and comfortable cruising than top end. The online caculators have come up with anything from 23P all the way down to 15P. Unfortunately here in NJ boating season is about over and I will be winterizing this weekend so no testing until spring. Just doing my research so I can be prepared for spring. Any advise is greatly appreciated.