What is the best method for matching flames from one side of the helmet to the other. I have 2 helmets and the flames need to match on all 4 sides. I am very picky, and I want them to be as close to identicle as possible. I am doing the positive/negative flames so there is alot of taping to be matched. I have 1 helmet done so far, but I did it the hard way, Eyeballing it. Save me please.