I missed the tires comment... but I was sure you weren't going to keep those old things on there.
As for the fan... that's just for a cool factor. I know you really don't need one although it does keep temps lower. I have a bunch on MM in several cars and setups. It's a potent little thing.
I'd like to see what this thing weighs when you get her all done. Should be one of the lightest Jato conversions, and well balanced too. I know one guy who has one that weighs almost a full pound more than a T4.