I was conserving how to calculate an eight bar height because the sight I usually use is down and I can’t find any other threads about it.
Can a mod please switch this to the unofficial forum clicked on wrong one. :o
I just use a lot of right triangles, trig, and parallelograms. Draw lines and use those to help you out. Also, there are 2 holes per inch, so convert to inches to calculate height.
I really don’t know calculations, so I just slap one together and measure 
For me it usually works to eyeball the spacing and not use any calculations. Or if you feel adventurous CAD it.