if you go to above 70watt bulbs for high beam you definitely want to upgrade your wiring, i fried the crap out of mine at first :)
i would recommend (same thing an auto elecy did for mine) adding in 2 relays, low beam and high beam, so that the wiring which comes from the interior of the car is used simply as a signal, then the hot 12V goes from the battery through the relays coil directly to the lights. also use a ~40amp breaker from the battery to the relays. the12volt.com always helps with stuff like this too. goodluck!

when i upgraded (learnt the hard way)
tech wiki lamp wiring

edit: if anyone has installed HID's some pics would be great. they are a bit too expensive to blow the $ now, but something i will do in the future..