Comment: I jumped the gun a bit on this idea, but overall I still think it is valid. I think ETH might have the potential to head to $510 if it hasn't hit its high (it is the 61.8% of the last down move, which is the maximum retracement of the A wave that B can make and still be a valid ZigZag pattern). Any higher than that and the idea as it is isn't valid and I'll need to rethink it.
That doesn't mean that it NEEDS to hit that, but it should be the allowable maximum.