how can i use the psp 3000 ver 6.38 downgrader ?

[SharukhKhan]

please tell me how to put the 6.02 or 6.35 fw in psp and can i play iso games in them and which one is good 6.20 or 6.35 and where can i download the fw 6.35 or 6.20 from please tell me with detail how to use the new 6.38 downgrader correctly and will it work on psp3004 and for mr toy how to u select the fw on the basis of motherboard thanks!