Hi Ice

Sounds like you are pretty much on the mark with your plans. Servos sound more than adequate. Your bird is likely to be pretty nose heavy with that engine, and the servos installed by the book. You might think about dual elevator servos, mounted aft. Search my name this thread, and you will see detailed pics of how to do it (with two different R70 builds).

Good luck with it. If you have specific questions, ask!

Bill