If you do have your parts galvanized , you might want to get PPG's DX 520 : Metal Conditioner -
DX 520 is a Phosphoric acid based coating chemical that will produce a zink phosphate coating on glavanized or steel surfaces .
DX520 contains a small amount of detergent which aids in the removal of light soils and oils and promotes the formation of a uniform zink phosphate coating.
DX520 is light green in color and may get darker over time.
Then spray the DPLF over it for an excellent ground base for your primer surfacer and color/clear !
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