This might be an expensive solution...but I would recommend looking at some of the better LED lamps available. If you have ever operated HID lights and noticed the improvement over standard halogens, I can tell you that the good LEDs are an order of magnitude better than the HID's. It's totally unbelievable until you see them in action. If you go the route of adding on more halogen or HID lights, watch your available power on the alternator,especially if you have a more modern drill with electrical parts.
RE340681 is the hood lamp that should work on a 50-series, but check with the dealer.