Practically speaking there is no difference between a gas stovetop and an electric one they must both be cleaned the same way.
You must thoroughly clean all parts of the stovetop including scraping residual food from the surface and catch-tray. Then refrain from use for 24 hours. Then you must turn the fire or coil to its maximum temperature for one hour.
You should consider the knobs not kosher and have a set of Passover knobs or cover them with contact paper. Some opinions say you can immerse the knobs in boiling water after thoroughly cleaning them and waiting 24 hours. You also should not place Pesach food on catch trays and all the areas between the burners. These things should be covered with foil to prevent direct contact of your Passover food with these surfaces.
