If your plans show 1.5 degrees negative on stab I'm curious why it would not indicate wing incidence? The 4 degrees the engine is down is not wing incidence that is engine downthrust. I'm at a loss as to why they would provide those 2 bits of info but ignore wing incidence? If decalage is stated that is the angle difference between wing and stab. Perhaps the wing is automatically fixed by the manner it's mounted.