What engine are you using? After many test flights, cumn thru determined 3 more degrees of right thrust were needed with a Saito 100 and 4 degrees with a YS 110. If I recall 15X4W and 16X4W APC props respectively. This was for extreme 3D flying, He never mentiond the need for up or down thrust. Ernst thrust plates were used to achive the results. I have 3 degree Ernst plate in mine (Saito 100), you will be able to tell more when you fly the airplane. I had one once that needed some additional downthrust and used a 1/16" piece of aluminum bar stock placed behind the top motor mount bolt holes. Worked like a charm, good luck with yours...