Hi,
I use a 5hp Honda. A problem I've experienced is even when locked in the vertical trim the O/B leg can hit the leading edge of the rudder. To overcome this I've machined off some of the cavitation plate from the engine but it can still occur. In the first season this caused the rudder to split, it is now reinforced over the joins of the two moulded sections. But still it makes occasional contact. I'm not sure when, but probably when undersail in a biggish sea I think as opposed to when under power. The reverse gear locking devise works correctly.
If I were to put the wooden mounting pad forward of the stainless steel mounting plates, this would set the OB to the fwd end of the OB hole in the hull, would this work?