Well good luck with the DRL relay. The wire data clearly shows that relay ties to the high beams. The low beams are tied to the HEAD LIGHT relay. Since you state you have no signs of power to the four fuses then the trouble is most likely due to a connection problem on the bottom side of the fuse panel. Those fuses tie directly to the battery according to the drawing. Power comes from the battery, through the fuses and on to the relays and lights. It’s possible there could be a problem with the relay (I doubt there is) but until power gets connected to them you have will have nothing no matter how many good relays you replace it with.
EDIT: After checking the drawing again I see I overlooked a key item. The four fuses not getting any power to them tie to the battery through a fusible link marked FL2. This can look like a normal piece of wire but really is a type of fuse calibrated to handle a certain amount of current load. That link is most likely open and needs to be replaced. It looks like the link ties to a blk/blu wire possibly.
I appreciate the support for easy solutions. Yes, I’ve checked the bulbs. I’ve pulled them out and looked at them. I’ve dealt with many blown bulbs in my day, as I’m sure most of us have. Besides, the headlight fuses aren’t getting power. I really don’t know much about electronics, but wouldn’t they be getting power if it was the bulbs?
Cougar, that’s intriguing. Out of curiosity, what is the point of having a fuse on the way to the fuse box? Assuming this is the problem, it looks like these are relatively cheap but a little harder to fix. What’s the best way of diagnosing if this is it? Replacing it?
Some fusible links have terminations on them and can be swapped out easily. Some have to be spliced in. I don’t know what type yours is or where it is at. It might come off the main battery cable to the starter solenoid or the battery post. To check it you look for voltage on both sides of the link connection. If it is blown out the battery side will have voltage on it and the other side won’t. They blow out in the middle of the wire and often appear to be just fine looking at it. By flexing it you can tell when it is blown out. The middle will flex easily since there isn’t any wire left there to make connection. Be sure to replace it with the same size link. What are the chances the link is causing the trouble; I would say 99.9%.
Remove the Head (light) relay and check for power and ground at each pin. Next lift the headlight relay 1/4" and ground the #2 pin, if the lights work this will confirm that everything after the relay if functioning.
Use caution when trying to actuate the relay, if you ground the wrong pin you will blow the fuse(s). I use a cheap test light (with an incandesent bulb) to test/trigger relays, if I touch the wrong pin it won’t blow the fuse.