First off, you need 2 PS3's. One one the newest firmware, and one that is jailbroken on 3.41. I doubt that you have these essentials so I will not further elaborate. If you do, I may continue.

Im a Newb to this too but maybe a little further along in my research than you.

OK you need to know these things and research around them.

First you need 2 PS3's one of which that has not been online for a while and still has the firmware 3.41 (or 3.55) and one running 3.70 (2 now)

The older PS3 has to be jailbroken (First point of research for you "How to jailbreak a ps3 on 3.55 or lower")

Then find out how to apply the patch (such as Elite Mossy V to the jailbroken PS3

Then Transfer the patched files via a sata Cable to the new PS3 running the latest firmware replacing the old MW2 Data file i think

You need to also have that newer PS3 Running on Bypass. This basically involved downloading an application that blocks the PS3's IP address and allows you to use the 1.11 patch not the 1.12 patch (Research how to bypass mw2 ps3)

If you do that then you will be at the same point as me where I think the only thing stopping me as the previous poster said is not having the second PS3 then you can come fight me on EBAY for old ps3's ....

Hope it helped

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