PW2 How to hack PW2 5.4.3 ?

Hi, I'm newbie
About two weeks I received my PW2 & upgraded firmware to 5.4.3
I want to install jailbreak and extend function?

My question?
1. Can I turn ON/OFF light completely?
2. What is the exact procedure for 5.4.3? (Consider newbies)
3. Is it possible to corrupt the kindle during jailbreak installation or no need to afraid?
4. Tools in this site is suitable for all type of kindles?
5. After successfully (or not successdully) installing jailberak, could i Re-Install 5.4.3 original image?