How much amperage do you think GMC headlights pull?

[RichardJ]

I thought about two fuses, but using this junction block, I can disconnect either or both relays.
The factory harness runs left to right in the photo, behind the relays under the fender lip.

I cut the green wire and crimped insulated single spade connectors to both cut ends. A short pigtail with spade connector connects the one green wire to the relay connector. Another pigtail with spade connector from the relay output, connects to the other end of the cut green wire.

If the relay should fail. I can disconnect all the spade connectors and plug the two green wire ends back together. Power for the headlights now comes directly from the dimmer switch to feed the lights as it did originally. If you should try this, you have to observe which male/female connecters are used and where.

I did the same with the tan wire and that relay. I did this some time ago and do recall that one of the Hi/Low wire(s) was doubled coming out of the bulkhead connector. Can't recall which, but if you say green, it probably is. I just stripped both wire pairs and crimped them into the same spade connector(s).

Sorry, I'm too lazy to go out and move the truck back and look under the hood.