Continuing my life story:
This cookie tray was too small to have the xbox sit in it, so I placed it sideways.I lined the tray with aluminum foil (shiney side up) to help reflect the heat upwards from the bottom.

I pre-heated the oven to 150, and placed inside with the ram chips in front of the GPU facing the door, as I didn't want direct heat on that section of the motherboard from the fan as the sync and eject buttons were on this side. This is probably overkill, but better safe than sorry.
I put it in for 150C for 1 min, 180C for 1 min, 200C for 1 min, and 230C for 5 min. The cooking went well. There was no smoke. The duct tape melted, but it's strong, so it held together nicely. I didn't get any brown spots on the board from inappropriate flux, like I have seen on another post.
Afterwards, I turned a fan on in the room, opened the windows, and left the door ajar for a slowish cool

Once cool/warm I took the box out the oven...

I slowly began taking it apart. The aluminium tape held down VERY nice, and didn't leave any sticky residue. The blu-tac also held it's ground, but became sticker. I found the best way to remove it was slowly pull it along it's path, and then dab and roll off any excess with a remaining piece of blu-tac. After removing, it was barely visible that it was even there on the first place!

I re-apply thermal paste, add two nice big 1mm washers I found onto the GPU RAM with double-sided thermal tape. I have seen many people fix these with a lot of thermal paste, but I tried this once, and it didn't work out very well (the washers kept falling out when screwing on the heat sink) and posed a risk of electrical short.

I then put on the CPU and GPU heat sinks. 1 metal washer under the board, 1 nylon on top, followed by another metal washer, then the heat sink (these are all the washers I have available to me). I also added some extra heat sinks on the RAM, the ANA chip (yes, I learned the name

) and a couple others. These were fixed with more double-sided thermal tape.

I then apply RBJTech's heat shroud mod.

I Was able to play COD3 for over an hour (then I had enough). Wasn't able to play for 15 minutes before RROD before! Xbox is in the bottom-left of the image.

So far so good

I also found some interesting information:
http://www.nexlogic....-Soldering.aspxQUOTE
"The lead-free alloy used for BGA solder balls has a melting point of 217ºC and requires a minimum reflow temperature of 235ºC to ensure good wetting. Maximum reflow temperature is in the 245ºC to 260ºC range, depending on complexity and density of the board."
So I wonder if the oven got hot enough...I am not even sure it reached 230C... Perhaps it should be cooked at 245-260? Also, my oven may be rather slow at heating up...but I didn't have an oven thermometer to check...but regardless, it seems ok for now.
Hope this helps anybody else who is puzzled.
Thoughts?