First let me start by saying thanks to everyone who replied to my email about how to actually do this correctly, it works and once you think about it makes lots of sense. Clive came over this morning to lend a hand and we started by lifting the nose of the plane to set the internal spar box at 0 degrees. Once this was established we ran a string line between both wing tips, see image 1, the string line follows the spar centre line very closely. I then dropped a plum-bob down from the string inside the fuselage onto the spar at the centre of the aircraft I am about 5mm (less than a 1/4 of an inch) in front of the centre point of the spar box. To change this would require the wings move to the rear about 1 to 2 mm at the tips. Because I had already drilled my rear bolt hole I decided that it was not worth doing, its so close its not funny and the plans give an error of + or - 50mm, so I figure I'm OK.
With the nose lifted and the spar at 0 degress, you can just see the string line between wing tips
The nose chocked up to set the spar at 0 degrees
Looking at the string line in the opposite direction
