What size Igloo cube for a 6 gal carboy?

My first beer in some time is sitting in the basement. No apparent activity for over 72 hours. I suspect the temps are a bit cool to start fermentation. I'm thinking of placing the carboy in a cube cooler and fashioning a foam lid similar to a photo of Yooperbrew's.

My carboy is 6 gallons, and I believe Yooper's was 5. The photo I saw had a lot of room, but the cooler was a huge model. I see an Igloo Ice Cube 50-75 Can Cooler at Target.com. It's out of stock, but the price seems good (for my next brew, I guess).

Will a 6 gallon carboy fit in there comfrotably with room for ice bottles? Anyone have this one?

I can fit a bucket easily in a 60 qt igloo from walmart... not what you asked, but for what it's worth....

Can you get the diameter of your bucket? Maybe I can compare to my carboy.

I see lots of posts for these for mash tuns, but not a whole lot of info on using them for fermentation temp control.

I have a desk air conditioner, which puts out a pretty pathetic stream of cold air, but I think if I piped it into the space between the cooler and carboy, it could give me a decent cooling. And a Brew belt would do for warming.

I just received a 70 qt. Ice Cube cooler from an off-shore seller through Amazon. My understanding is that it will fit a 6 gal. carboy with the same type of lid that Yooper's has.

I'm looking forward to experimenting with it.

I've got a 60qt igloo ice cube and my 6.5gal carboy fits fine -- just had to make a few modifications to the underside of the lid to allow the top portion of the carboy to fit snugly -- also have my airlock ported out. I use no larger than 32oz. (usually 20oz) water bottles to cool my brew, but I don't think a full size 2 liter would fit with the carboy in the center of the cooler.

I hope this helps..