Assuming is emquiry is referring to Rust-Oleum 3369/3380 CombiPrimer Anti-Corrosion and Rust-Oleum CombiColor Original, the previously painted surface is clean, dry, sound and prepared as detailed in the technical data sheet they may be used for this application.

These products are designed for light industrial applications where anti-corrosive primers and topcoats are required, but these are not classed as automotive paints specifically for use on vehicles.

However customers have had good results with this products when applied to hobby vehicles, although it is not something we or the manufacturer can offically support.

We would recommend testing for compatibility and adhesion on any previously painted substrates prior to application.