Mmm......not sure what else I can help you with,presumably your keeping the aircraft trimmed out and operating the engine manifold at the respective 42 inches and RPM at 2550 ?......try only using 50% fuel,I may be wrong,but I think this helps with the balance too.I'm personally not having the issues you are witnessing.
Re the elevator trim,this is implemented,and it works for me,I'm using the old Saitek Cessna trim wheel,which has it's own Axis,it works a treat.
The P-47 was a very heavy old bird in comparison to the P-51,so the two FM's are quite different obviously.