"As with my original intent to ferment seven gallons and bottle six from my 13.5-gallon garbage can, I'll ferment eight gallons with this bucket and bottle seven. I have enough 500cc bottles to do it. I'm willing to sacrifice the one gallon below the spigot to keep the dead yeast out of my bottling bucket."
If you put about a 1" shim (book, board, etc.) under the back side as you transfer to the bottling bucket, I think you'll get more of the beer and still leave the dead yeast out of the bottling bucket.