First, you're shooting too light of a spine for that set-up, unless you're shooting a 25" arrow, that .400 spine too weak. For that set-up, a 340 left at about 29-29.5" w/ a 125gr tip, and that would get the spine closer to where you need to be. From there, best thing you could do is QUIT trying to paper tune, because in many ways, it's a bit of a waste of time, and paper tuning is only as good as your release and follow through, and your BROTHER needs to be shooting that bow to get it tuned best for him, not you. If you want to use those .400 spine arrows, as BG says, you need to be down around 60-63#'s to get the spine right.

After that, zero a pin at 20yds, get consistent groups, at 20yds, do a walk-back tune, making sure the rest is centered, then try to BH tune. If you're shooting through a WB, I wouldn't shoot anything but Blazers or another very stiff vane through it as you want something that will tolerate the abuse of shooting through a WB. For me, I've found that I can generally eyeball a set-up, and make no more than 3-4 fine adjustments and have a bow BH tuned, and a STIFF arrow is always easier to try to tune to a set-up than a weak spine.