Let's see if we can work this out together, I'm more than willing to do so. Will need to forget all about AV plate sitting on a dry installation as all engine owner's manuals blindly recommends. Dry engine setups most times doen't work properly once boats are tested on water at speed/plane.
Regarding inflatables for a perfect setup you have to deal with tubes diameters, transom heights and engine brands, all of which doesn't match between fabricators. Imagine all engine brands fabricating a dedicated engine that matches all inflatables sib/rib brands models.
Go to the other side of the pond and read this new post, has new info added, let me know if you fully understood at least the plain AV plate brand theory starting second post.
Opt Engine/Transom Height - iboats Boating Forums