I am having a problem choosing what size throttle body to use. They are all the same price too which makes it even harder. My first thought was to go with the bigger one which is like 70 mm, but i wasn't sure because they have a 66mm and a 68 mm. These are all skunk2. I kinda want a majority of my car to be skunk2, i just like their products. But any info would be appreciated on which one to go with.