when you align brush hoods it doesnt have to be straight across , you want to check for brush wear (+)and (-) side ,,, to make sure that the brush is wearing even across the com ,,, after you break in the brushes for 5 min look how they are wearing out and make adjustments based on what you see,,, how to tell when the brushes are wearing on even across the com , you pull them out after breaking and usually you see a dark side(carbon build up) and a bright side on the brush that means the brushhood is not align correctly.