Heat them from the center out in small increments and use a metal shrinking hammer and dolly working from the inside out until you get the metal flat and back into shape. I've done this with many heavy metal surfaces and had good success.
Tim
"Pay attention to the details! It ALWAYS pays off."
1949 Chevrolet 3100 Series 1/2 ton Pickup 1964 Chevrolet C10 (Ol' Yella) (SOLD) 1958 Chevrolet Biscayne 2 door (SOLD) 1970 VW Beetle
