Yes, as long as the previous finish is not lacquer or shellac. Be sure to test the selected colour on a hidden spot to see how it will look over the original finish. To prepare the surface, make sure that the finish is clean and has had all wax and polish removed. Then lightly sand with #180 or #220 sandpaper.
Then thaw meat, add seasoning and press into strips or sticks, and place on trays to dry. Depending on how thick meat is cut, how heavily dryer is loaded, and the humidity, jerky takes from 4 to 15 hours to dry.
Put your trays of meat in the oven and just forget about it for several hours. The drying time will depend on the type of meat you are using and how thick you have cut the slices. Typically it will take at least 8 hours to fully dry. Perfect jerky should be firm and dry but still pliable.