i just painted some door handles and other parts with sem paint its called color coat aerosols its flexible paint not dye u can use it on carpet,seats and other interior parts .just where the sun bakes the top of door handle and turns it dark color well its gone . the paint covered up great and i am very satisfied with the results but 1 can of 12 oz paint cost around 28$ sem sent me a color chare they carry 3 different blue colors.866-327-7829 call them and get hem to send u a color chart and on your dash vents i would put 1 or 2 coats so the grain will still show the more the paint the less u gonna see the grain. good luck on your project