Another CSS related problem, please help!

I have installed the infinite scroll plugin for my wordpress blog


basically it will eliminate the next/previous button and there will be no more clicking to next page, it will display more posts as you scroll down.

But I'm not sure how to setup the following parameters (basically I can't find the correct div and I can't seem to make it work):

Content CSS Selector: (The selector of the content div on the main page.) my input: #contentIndex

Post CSS Selector: The selector of the post block.

Examples:
#content > *
#content div.post
div.primary div.entry

my input: div.eachpost

Navigation Links CSS Selector: The selector of the navigation div (the one that includes the next and previous links).

my input: div.navigation_group

Previous posts CSS Selector: The selector of the previous posts (next page) A tag.

Examples:
div.navigation a:first
div.navigation a:contains(Previous)

my input: div.navigation_group a:first

Again any help would be greatly appreciated
darkmobius