EDITED !!

w8ye, no I'm not fallowing you around LOL,,

the Gassers I have worked on (from 73 inch span to 82 inch) called for the Back of their Props to be mounted 6&1/2 inches from the Engine Wall, and these Planes called for at lest 2 Degrees of Right Thrust,,

it's very easy to use a Protractor,,
with 2&1/4 Degrees of Right Thrust/Back of Prop 6&1/2 inch from the Engine Wall you will need an Engine Offset of 3/8 inches,,

and it may also be a good idea to give half that in Down Thrust..

if you have the Prop distant to Wall, and the Thrust Angle numbers you need then all you need is a Protractor to get the Offset,,

then set your Engine on the Wall and mark your holes..


Jim