I believe the infamous "bulb out" sensor only monitors the low beams; as mentioned by others, you'll lose the functionality when you put in relays. That said, you won't miss it - you'll notice when one of the 80W low beams burns out!

What you'll end up doing is to add an additional wiring harness, fuses & relays, using the existing headlight wiring to power the relay coils via terminal #85 on the relays.

I've done this conversion on my 740; most folks use separate matching relays for each side of the low beams, to keep the sensor happy. I used a single relay for low beams and connected both sides of the OEM headlight wiring to the #85 terminal, with a diode in line on each side between the wiring & relay terminal. This isolated each side from the other, yet balanced the current fed to the relay from each side of the OEM wiring thus keeping the "bulb out" sensor happy & the warning light off. The voltage drop across the diodes (about 1 volt) hasn't affected the operation; the relay coil seems just as happy at 12.8 volts as at 13.8 volts.

I've also wired the H1 bulbs as separate driving lights & used a Volvo OEM driving lamp switch (they call it a "spot light" switch).

Don't just rely on crimping the wire terminals - solder them as well! You're going to be drawing a LOT of current to power the bulbs, and you want the best connections you can get.

For best instructions & generic wiring diagrams, check out Dan Stern's automotive lighting website.