ah...from that you've said that you've replaced both the front door switches, yeah? when he installed them did he give them a good clean, i mean between the switch and the body, and that light is controlled from ALL the switches, so i'd check the back ones as well. Just take all the switches out of the car and see if it turns off, the switch works by putting earth onto the wire at the back of the switch, if the globe doesn't turn off then, you'll have a short to ground somewhere in the circuit. But in my experience 90% of the time it's the switches.