[68jimmy]

The whole reason to install relays is to provide a higher amperage to your lights thereby increasing the amount of light. This also keeps the increased amps out of the headlight switch and corresponding wiring.
Sometime ago prior to getting hooked on these trucks I owned a vw jetta gli. I installed a set of european lamp assemblies with H4 bulbs that were rated at 85/80 watts. I did much of the same except that each headlamp utilized two relays, one for high the other for low for a total of four relays. The factory wiring was used from the switch to the relays then from the relays I used 10 guage wiring for both the 12v and ground connections. Seems like overkill but I wanted to be sure that when I had my high beams on I wasn't going to melt any wires.
To calculate the amps your headlights will draw use the following: Amps=watts/volts. So for a 55/45 headlamp using the equation gives us: 55/12=4.58. Together your headlights on high beams will draw approximately 9amps of current. Using that information you can now select the proper gauge wire to use from the relays to your lamps and your grounds...

Good luck!