I modified my 3.01 Devhook Firmware Installer so that you can install any update that is supported by the latest devhook.
In words this mean you can install
2.80
2.82
3.01
3.02
you decide it
Usage is the same as ever:
Download latest devhook and install it.
Install this Installer
Download your desired update (2.80-3.02) and place it in the root of your memory stick, and name it "eboot.pbp" if it isn't already named like that.
Then in the XMB choose "Devhook Firmware Installer".
Once prompted hit [X] to install the firmware for devhook
Wait till PSP reboots and fire up devhook, choose the firmware you just installed and reboot.
Done!
Changes from the 3.01 Installer
-support for 2.80-3.02 update (not hardcoded to 3.01)
-support for 32MB memory sticks
-improved gui (nicer blue :P )
-EU/US button layout, unlike the 3.01 installer which had the JP button layout
-improved errordetection
This is based on code from PspPet, Dark_AleX and Team Noobz. In no way does it read or write from your onboard flash!
Tested by me on 1.5 with 2.82,3.01,3.02 update and latest devhook
It may support newer updates aslong as sony doesn't change the keys (again) and of course devhook supports it