Ethereum Pre-Sale extract SAFE hash (non-revealing private keys)

[Johnsnowkadost]

Gonna check for the encseed content on some example wallet and will update you. But assuming to take the bytes of the seed - 50 characters it should be safe ? 
Also I took a quick look at this assuming it's the https://hashcat.net/wiki/doku.php?id=hashcat_utils for the padding checks and I didn't really get the entropy stuff (would spend more time on it). 

The only issue is that I don't exactly see how I can implement it in what steps basically ?  

My idea be something like this I guess :
1) Substract the last x char of the encseed 
2) Apply the SHA3 (I'm not sure)
3) Check the padding (Not sure too)

Thanks again for you great response