I am new to this and have an 05 S40 with the white spacer removed and a drop in K&N filter installed.  I have drilled out the brass plug and adjusted the screw to match the filter.

I also have a Xenon H4 headlight, well worth the money by the way.  I was wondering how any of you on here who have the outside casing of the engine, which on mine is painted black with aluminum or chrome edges, to be all polished chrome.  I would love to do this but do not want to spend an arm and a leg on it.  Let me know how this is accomplished and if it can be done on an 05.  Thanks,

What I have seen on this site goes far beyond just sanding down the aluminum and polishing it.  This is more like buying a custom chrome cover or something to that affect.

The case is Aluminum, which polishes up nicely.

The engine paint its hardcore stuff.  It has to be, the engine gets real hot and can get oil spills.  Plus road stones...  so, it can be hard to get off.  

Also, Chrome needs a farily smooth surface as a base so the polishing is almost needed anyway.  And, chrome plating is pricey.....

If you still want to attempt it,  try some spray can paint remover.  The local Auto-Zone here carries Aircraft paint stripper which works geat.    You may want to try is somewhere hidden so that if it doesn't work, it can be touched up and still not be noticed....