I am trying to figure out the correct x-d for a twin outboard with a bracket. The offshore hull 30 ft longand 8ft wide, and 24 degree dead rise. Any help would be great.

with out seeing it its going to be hard to tell you what the rite number is..take into consideration first is whare your water pick up is,,how long your lower cases are and it can go on from their..

The motors are 275HP Johnsons with lwp and nose cones. My next question is how high should the plates be in relation to the bottom of the boat I heard that they should be 2" higher??????????