You want to "lose" eight spokes and it's turned into this? You have all the math- use the info. If your math didn't work out and the first assembly wasn't quite right, buy some more spokes and try again. That's how most of the builders around here learned. You want free advice? Play nice.

I think I'm thinking the same as the other respondents- why? (though I won't speak for them) You already know the spoke length for 36 spoke (and pattern) on that hub and rim. Just rebuild it. If you want 28- buy the appropriate huib as well. If you goal is to lose weight- 8 spokes at 4 grams each ain't dog doodoo. And... Dura Ace hubs ain't that light compared to some of the others. You ain't gaining squat.