you really are good at art ! i believe that angle is the "anti dive" angle, which, if i'm not totally out there, is to prevent front end drop when the brakes are applied. this is in relation to the plane of the lower control arm. it will stay as the engineers designed it if you keep the upper arm as your drawing shows. it may be 90* as in the illustration, but could be a 2* or more tilt to the rear in relation to the lower arm. as you said before, this will get you at the original ride height. from there, you can lower, or raise as you see fit, but keep the upper arm angle the same as it was in the dak chassis.