I've got the same set but in purple! All the long ones are for the plenum. I than just worked my way around the bay removing bolts and placing them next to the new ones to find out which size to use. There should be a rough diagram on the ebay page to show the areas the bolts are used.
You can use this pic to help:
http://i.ebayimg.com...EZG/s-l1600.jpg