Not a Moomba but need prop advise for my fishing boat

[JPAGE]

I have a 1980 Mako 236 straight inboard boat specs are:

weight 3800lbs may be heavier due to wet foam
engine 5.0l Volvo Penta 220HP max rated RPM 4800
dead rise 16 deg.
8ft beam
now turning a 3 blade 14x11 prop W.O.T 4000rpm or so
cruise 3000rpm at 19-23MPH depending on load

I have as a spare an OJ prop that is 13X13. Was thinking about getting it re pitched down to a 13x11 . How would this affect the cruise/ fuel economy would this give me some more W.O.T rpm?? Should i have a different prop all together?? I care nothing about top speed. I would like the best cruise speed/ economy i can get. This boat loaded with full fishing load i estimate at ~5500lbs
Boat:
http://i95.photobucket.com/albums/l151/SpedJunkie/destin%205-17-10/floridamay17th014.jpg
http://i95.photobucket.com/albums/l151/SpedJunkie/Destin%20Mako%20week/236DESTIN1.jpg
OJ prop to be "Tuned"
http://i95.photobucket.com/albums/l151/SpedJunkie/1980%20Mako%2023%20inboard/prop002-1.jpg
http://i95.photobucket.com/albums/l151/SpedJunkie/1980%20Mako%2023%20inboard/prop001-1.jpg

[kaneboats]

Give Eric at OJ a call. They know every application and every product they have. He's on here fairly often and very helpful. You can also PM him on this site. He's: ejojprop

[New Guy]

Oh man, load that thing up and get out there surfing!!