Welcome to RIB.net
Where the cavitation plate is located in relation to the bottom of the hull is the important part. Got a side photo of the two? Put a straight edge on it too. More correctly it is a running at speed check, and the location of the spray plate, along with any cavitation/handling issues. Each hull design is different.
I have one of those fins many will say do not work well, but for diving they work awesome for keeping the boat on plane and getting it there. You have plenty of horse power though.