The systemctrl.prx is for the psp phat.The systemctrl_02g.prx is for the psp slim.Now go to your psp's VSH Menu by pressing select in your psp xmb:
Set your USB Device to Flash0. Now exit the VSH Menu and connect to your PC via USB.Open up My Computer and open your PSP drive. You should end up with your PSP's Flash0 folder screen like this:
Now double click on the km OR kd folder, depending on your firmware, and you should see a screen with alot of files like this:
This is where you place your systemctrl.prx OR systemctrl_02g.prx file, depending on your psp model.Once thats done you need to enable the patch by telling the PSP to run it by modifying the pspbtcnf_game.txt & the pspbtcnf_updater.txt text files contained within the same screen folder.You do this by entering this line of text: /kd/mspatch.prx after the line /kd/msstor.prx.
Do this for BOTH pspbtcnf_game.txt & the pspbtcnf_updater.txt text files. Save changes and close all windows. Exit USB mode and voila! A 8gb compatible psp.Note: You need to install the 1.50 Kernel add-on before installing this patch to the firmware if you are on a phat. And remember that you'll have folder km instead of kd in some psp cfw.[SIZE=3][b]Note[/SIZE]: You need a MS inserted in your psp when you install the patch files or your [SIZE=3][b][u]psp will brick[/b][/SIZE]. D'oh!Also take note that this involves writing your psp's flash0 so if you do not know what you are doing then you could brick your psp. You can of course use Pandora&MMS to re-vitalize your psp but there are tutorials already written here in the forums on how to go about that.All in all. I hope this tutorial helps you out and GOOD LUCK!