Re: engine painting
Cylinder head, no problem.
The muffler might be a different story. I'd probably use a high temperature paint on it. If it is the chrome plated one you'll have to rough up the chrome before paint will stick.
I've never tried to paint a chrome muffler but I have made custom exhaust pipes from EMT, electrical conduit. I use a high temp engine paint, silver, on those with good results.
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