If you have Installed this on 5.00 M33-3 or 5.00 M33-4 you dont need to do this again.
if there isnt a folder called 'ISO' create 1, but make sure it is 'ISO' ( without the ' s ) now put the game that you jsut ripped into that folder.
When it gets to the end, you might get a blue screen with in a couple languages saying a warning, if you do, it means you have a custom theme installed.
Shutdown your PSP manually after that screen disappears and then turn it back on. When done, you now have 5.00 M33-6 installed on your PSP!! Now if you have a Phat PSP ( PSP-1000 ) make sure you have loaded the 1.50 Official Firmware above and the kernel Addon.
Now people with a phat PSP can play homebrew on their PSP!!
Hope this helped someone, if you have any problems, just comment here or send a PM =D ill put some images up of the installation of both 5.00 M33-6 and the 1.50 installer, when i have time =Dnice work man seems the psp documentation is being greatly upgreaded since the lot of new guides posted recently.