Regarding bumping ads in the classifed forums, we've just installed a new (customized) add-on that will change the way ads are bumped to the top. Please refer to the post "Bumping Classifed Ads" for details.
I've looked at several parts breakdowns that show I should have serrated washer that faces against this end. What the pics aren't showing is what the inside of that washer looks like. Is it just serrated or does it have protrusions that fit into the slots of the center thingy?