Sure. Let me try to answer your first question about the factory compression ratio, since that's the root of the issue.
Chrysler was really inconsistent about certain machining tolerances. Cylinder block deck heights were taller than spec, combustion chambers were larger than spec. That 8.4:1 compression ratio was an advertised rating. See that word advertised? Yeah. Marketing. These engines usually blueprinted (true measurement) closer to 1/2 to 1 full point below their advertised rating.
