Get the exhaust coated with Jet-Hot by brand name. It is available in many colors other than silver that is most common. There is a gray/black that I think would match your desires. It will cost a liitle more time as they run colors in lots and the most common get done first.
Check web for dealer in your area. I swear by this product and have begun having all tin work from engine like
oil pan, timing cover, manifolds, V. covers etc.. The engine looked great, is easy to keep clean. I can not document but believe lower
oil temp. and lower engine compartment temps are also the result. There may be other manufacturers with like product but I have no experience with them.
