First, you need three program to do so.
Eboot patcher v1.0 -
[You must be registered and logged in to see this link.]UMD GEN - Available in google
Yoshihiro's patcher v2 - Available in google
Instruction Steps:
There is NO need of a clean ISO for that. If you already have a decrypted one, just extract again EBOOT.BIN patch it with this new patcher and remake the ISO! Which mean, if you have a ISO file has already patched, then you can skip the Yoshuhiro patcher step and go on to Step 3.
1. Decrypt with Yoshihiro's patcher ( If you are not sure what is it, Follow this tutorial here - viewtopic.php?p=64613)
and Remove with UMDGen from the image game EBOOT.BIN loader and export the File list (menu File> File list> Export).
2. Eboot patcher loader EBOOT.BIN
3. Apply the patcher to Eboot patcher loader EBOOT.BIN (check that this is dekriptovanny - he heder ELF).
4. Pack the boot back into the image (with UMDGen replace the boot EBOOT.BIN in the image on dekriptovanny).
5. Import File list back, agreeing with the question of the desire zaforsit file locations in the image! (this item is required for manygames, in particular DiRT2 without this procedure falls into a black screen)
6. Save the new image of UMDGen (cohranite original)
7. Rewrite the image on the psp and play.
Gran Turismo working on PSP-3000 5.03 GEN :
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