One way to do this is to find out if there are any trig properties of 103.68 you can use.
180-103.68=76.32; 103.68-90=13.68; now we look at the tangent of these angles: tan(76.32)=4.11 approximately.
This means that if you draw a right-angled triangle ABC where B is the right-angle, AB/BC=tan(76.32).
Using graph paper, mark off a vertical measurement of 41.08 and a horizontal measurement of 10, both measurements made from the origin of the axes. You can use any measurement for the unit, inches, cm, mm as long as you use the same one for measuring the distances. The larger the unit you use the more accurate will be the angle, but you will be restricted by the size of the paper. You could also use the measurements 20.54 and 5 instead of 41.10 and 10 to fit the paper better, because the ratio is the same. As long as the ratio is close to AB/BC=4.10839..., the method will work.
After marking these points on the axes, join them together. Take the obtuse angle, external to the triangle, formed by the sloping side AC and the horizontal axis. That is the angle you want: 103.68 degrees.