OldColt has the chrome valve cover stick-ons and they look great. Much cleaner than the brushed/corroded oem look. However, with a bit of work, that can be maintained to look decent. I know, I've been cleaning mine for 15 years.
A company called "Appliance" made white headers back in the early 70's that looked pretty cool. Unfortunately they were spray-bombed (not powder-coated), were made of mild steel (NOT stainless) and showed off the " grimy black-hand" installation markings.
They looked nice for a week or so until the paint burned off and rust spots started showing up on the bare steel. Ceramic coating is WAY tougher.
SLITHERBEAST: Ditto with the steering bolt whacking the #3 primary tube. A wee bit of grinding solved the issue. The twisted flange on #5 required a bolt extender to turn it into place (almost). It was not unexpected but disappointing what with laser-guided measuring systems, precision CNC machining and 3-D printed burgers