Installing CFW on fat psp 3.72...need help plz

Ok so my nephew got a psp and I want to put CFW for him, I did mine around 2 years ago and don't remember everything.

so it's a fat psp, 3.72 original FW, it's a ta-082 (but that shouldn't matter since the newer cfw are up). Do I need to downgrade to 1.50 first then go to 3.90m33(or 4.01 w/e). Can I directly put 3.71m33 CFW?

Thanks!

Do you have access to your CFW psp still?

if so it make it much easier as you can go to http://dark-alex.org/index_psp.php and download the Despertar del Cementerio, each version does the same thing but puts a different CFW on the psp. You have to follow the instructions and run the program on your psp to make the Mem Stick. Then you need a "pandora battery". There any different possibilities when making or buying one of these if you dont have one.
After u run the program on your homebrew able psp, put the memstick in his psp and then the pandora battery. Follow the prompts and Poof! your done.

I think Despertar del Cementerio Version 3 does 3.71 M33, but not 100% sure.

Edit: ok that website above is not the one for the PBP to dl, just search for each .PBP file that you need.