It's been some time since I looked at the Wyvern plan so the airfoil shape doesn't pop into my memory. I do have a Mauler plan. A number of Carrier designs used something like a Clark Y section. One thing to remember, incidence isn't measured from the bottom surface of the wing. It is measured from the chord line. The chord line runs from the center of the LE to the center of the TE. So, when the lower rear surface of the Clark Y is parallel to the longitudinal datam the wing has positive incidence.
Without realizing it we probably trim in some down on most of our planes at high speed. It did seem that the Maulers I have seen looked like they flew tail high. But, no one ever said it caused any particular difficulty.
It wouldn't hurt to build the model with zero incidence.
Bob