If you need to paint the grille, then yes, you need to disassemble it to prep and paint. If it were assembled it would be a giant pain to get painted correctly. If you look at the photos I posted above, you can see that the outer vertical supports were painted body color, and the inner vertical supports were painted Waldorf White (Rustoleum Canvas White available in rattle cans is an excellent match) along with the inner bars. The outer bars were either painted body color or chrome plated. The usual vendors sell bolt kits for the grille, with domed head bolts (like carriage bolts but without the square below the head.)