Compatibility is not an issue when applying TotalBoat Elixir directly to fully cured latex paint. The latex paint should be cured for at least 5-7 days before applying Elixir.
The latex paint surface needs to be clean, free of any contaminants, then lightly sanded smooth before applying Elixir. It should be understood that latex paint is much softer than Elixir, and Elixir will cure to the exact texture of the surface of the latex paint underneath.