Help installing cfw on slim 2003

[Cloud]

Hi,
Been off the psp scene for a little while.....(been concentrating on ps3 lately)
Just a little pointer please.

I'm wanting to install cfw on my friend psp for him.
He's currently running a slim 2003 model with 3.90ofw.
My psp is a phat 1003 on 5.50 Prometheus 3
I already have Pandora battery and MMS
I'm I correct in thinking I can just use these to flash DC8 5.00 M33-4 straight to his slim,
Then update to Prometheus after.

Thanks