Alienware M17X R2 Overdue Upgrades

Okay, so here's the deal, I'm new to the thread, so hello. I've gotten quite a bit of info off this site, that's why I decided to join.

Next is I have some general questions about an upgrade project I'm planning for my M17X R2. I've already scoured the web and haven't found what I'm looking for so I'm going to ask directly.

My R2 wasn't top of the line, even when it was brand new, and it's just had 4th birthday. Obviously it's time to breathe some new life into it.

Before I get into the specifics of my plan let me say a few things,
one, I'm not asking if you think it's what I SHOULD do, I'm asking what I CAN do.
two, This laptop was a very expensive gift from my father and has sentimental value to me, that's why I'm spending as much upgrading it as I could on a newer, all around better laptop.
three, I'm not going for the benchmark world record here, I'm just trying to freshen up an aging machine with the best components (within reason) it's capable of supporting so i can get another 4 years out of her.

All that said, here's the deal.

My R2 has an i7 720QM, which I want to upgrade to an i7 940XM.
My research says that's totally do able. The socket is the same, the chipset PM55 (according to Intel's website) supports it, it only uses 10 more watts TDP, and the BIOS shouldn't have a problem with it either.

It currently has 4Gb of RAM, I wish to go to 2X8Gb GSkill 1333 (10600).
The processor and mobo only officially support 8Gb, however, I've found users who say it supports and uses 16Gb just fine, however at it's inception 8Gb sticks weren't available. Yes, I'm doing a fresh Windows 7 install. (Windows 8 just doesn't appeal to me, 7 is perfect, IMHO)

I want to throw in a 120Gb (small size due to cost) SSD and run my current 320 HDD as the secondary. That should be plenty for my games and I can use the HDD for movies, music, pictures, ie, things that don't need to be fast.

I wanna keep the Blu-Ray player.

And lastly, the biggest part that i have questions about, the graphics card setup. It currently has an ATI Mobility Radeon HD 5650M.
I'd like to either get it a matching card and go Crossfire, or upgrade to 2 5870M's and go Crossfire. So here are the questions:
one, what would this require? I'm tracking another card, Crossfire cable, right side slave heatsink, and right side slave fan.
two, what is the best graphics card the R2 supports without reflashing VBIOS, modding the case, etc. the 5990m? The 5870M? Does anyone know?
three, what the hell do I have to do software wise to get Crossfire going and all the new parts playing nice together? I want the project to be as plug n play as possible, with just driver updates to get everything working.

Please, let me know about the graphics cards and any known issue you see arising from the details I've spelled out, thanks!