340 oe-a to ofw help!!

[Afterburn]

Hey everyone I'm trying to help a friend out with his psp. I've never played around with a psp so all the info and different guides I have read and seen has just confused me

I'm trying to get a psp1000 cfw 340 oe-a to current ofw. Yes I said ofw lol not my psp
From what I read I can't just jump straight to new ofw or I can brick it?!? or can I ? I also read over the Ultimate cfw install. but followed the semi brick info but i get errors so im thinking its not the right route. Please any tips or suggestions on how to do this correctly :) would be great.

[elite999]

Use this guide. Section of "How to Reflash/update/downgrade Firmware (Semi-Bricked/1.50 PSP Users See Here)". Upgrade to 5.00 M33-6. After that, directly upgrade using XMB Network upgrade.