Strip your factory grips with E-Z Off oven cleaner and dry them completely. (Tape over medallions) Then apply one of the darker stains like Min-Wax Jacobean. Some of them are almost black in the can but the wood will not take on so much stain as to turn completely black. Apply the stain and wipe off with a clean dust free cloth. Reapply as needed. when you get to the color you want let the stain dry until the next day, depending on the humidity, and rub in several coats of Tung oil or Min-Wax floor polish wax. Buff to a high sheen.