Bruce, the problem is that the surfaces are not sitting flush.
Here is a pic.
The first thing is I don't know what it is called
It is the first piece that sits on the engine. The second is the old plate and the other two are new 2 and 2 1/2" plates.
The diameter of the I don't know what it is called is greater than the diameter of the bolt pattern on the new plates causing only the nuts two make contact with the I don't know what it is called
.
When I tighten the prop it deforms the plate because it is not flush.
Jeez! It's hard to explain stuff when you don't know the technical jargon.