Someone earlier in this thread mentioned using "Basic White" and 30 weight Hydrogen Peroxide. This is where you can avoid bleaching out the antlers. Just like you are mixing the baby powder with the peroxide to get at the top of the scull where it is not down in the peroxide solution...except you paint the whole skull with the Basic White and the commercial strength Peroxide.
PatB, you are definitely right about keeping the antler bases out of the water if you are boiling. BUT if you keep it below boiling, like OsageOutlaw does there will be no problem with bleaching out the bases. A pro taxidermist taught me that trick. He also advised I use distilled water and NO detergents, soaps, lye, or other shortcuts. Just keep the water around 200 degrees, that's all you need.
I've done a couple dozen like this and the below boiling in pure water seems to work the best of all. I use a hotplate out in the garage and try to keep the pot as covered as possible with tinfoil and let 'er simmer all nite....gooshy, gooshy head soup!