3) Install psardump02a in PSP/GAME (with kxploit for 1.50)

- For 1.00 firmware : copy MPHFL (in 1.00 folder) to PSP/GAME folder of your memory stick
- For 1.50 firmware : copy MPHFL and MPHFL% (in 1.50 folder) to PSP/GAME of your memory stick

so it runs on 1.5 and 1.00

- Load 1.00, 1.50, 1.51, 1.52, 2.00, 2.01, 2.50 firmware

it loads all other fw on 1.5 and 1.00, so you could have 2.5 fw running on 1.5, which is still really good