so after checking that the plan was accurate and re-draughting a few lines on it, I took the wing underside as a datum and transfered the down wash angle relative to this datum and came up with a 2 degree down wash from there. Then I build a jig that would position the motor mounts relative to the wing underside and at the same time hold them parallel to the fuselage centre line whilst the glue dried. It worked well and now I have my motor mounts correctly positioned on the wing structure, all the ducks in a row, one may say.
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