Single Sterndrive Offset

Hello, here it comes,the good old 1.000.000 $ question,hope someone is able to give an answer based on direct experience.
We are in the process of installing a single 450 hp sterndrive on a 25' Racing Rib.
The prop is a 28 pitch and the engine delivers 450 hp (+ or - ) @ 5800 rpm,reduction 1.5
Rib dimensions are:
25 lenght
6.3 beam (inflatables excludede)
8.4 beam including inflatables.
I have to mount the sterndrive with an offset to contrast the turning effect
created by the prop thrust and high power of the engine.
The prop rotates clockwise so i would offset it's location to port...and now the 1.000 k $ question: how much???
Once the hole is done is done and it's not possible to apply trial and error here....
Thanks to everyone who will give it a try as usual!

 

c'mon guys!! I know you can help me!

 

why not a BIII duoprop?

 

Thanks Yipster,we already took in consideration the bravo 3 ,unfortunatly we have to use a bravo XR capable of more than 400 hp bravo 3 limit is @ 400 hp (and it's related torque) and the engine delivers more than that (more than 450 hp)
Plus, Bravo 3 has gear rations from 1.8 up.