Or you could try cerami-coating your headers... ghetto style...

take off your header, wash out all the deposits in there with a strong solvent, some high-pressure water and detergent and an air hose... if you can get something in there to scrape it out (like a steel brush), even better... then fill the header with high-temp paint (those 1000 degree paints you see at hardware stores for burners)... swirl it around in there to get a nice even coating, then drain and let dry.
I don't guarantee the coating won't flake off and get ingested into your engine when you start it, though... there's a vacuum when you start the engine... which is why flaky cats have killed QR25 engines in the US... but it should do the same job that header wrap does.