You actually don't need to know any pvk Yourself but just for introduce You a specific method that You can understand or try at least, for a test purpose I needed to write everything like "we need" initial pvk to demonstrate but the cracking reality is simple : string from step6 + target address, no more details and I'll demonstrate how fast I am.
3.Convert the hexadecimal private key to decimal as well,
4 Now using a big integer calculator for example
http://www.javascripter.net/math/calculators/100digitbigintcalculator.htm ( I am also using it ) divide the decimal string of hash160 by decimal version of private key
So then how would you get that without the privkey from step 3 ? ...