50% or more. What's really important is to make sure it's a wet coat. With the mix you have now that shouldn't be a problem. You have to make sure you let dry enough in-between coats. I've heard you could get some mottling if you don't. I would shoot around the scoop first and then lay down the wet coats after. You won't have to worry about runs except around the scoop. Give her heck, it's gonna look good!