91 S-10 Blazer, no headlights & no power to fuel pump,

Take a good look at the condition of the connections at grounding points, particularly where a cable is grounded to the frame. Corrosion is sometimes hard to detect and it can drive you to wit's end. Also, inspect the negative battery cable terminal. I've seen corrosion build up beneath the insulation (where it's nearly impossible to detect) and cause a poor electrical connection. Good luck.

Thanks for the reply

Finally found the problem after taking out the entire dash. (Like they say: "Kids, don't try this at home") Turned out one of the two hot wires in the connection block between the engine wiring harness, thru the firewall and into the fuse block just decided not to connect. Nothing was visibly fried, corroded, broken or otherwise fouled, but still....

Picked up another wire and connectors from the local Pick n Pull and swapped 'em. Only took about 5 hours to get everything back together. I'd hate to see what a shop would have charged me to find n fix it. Probably would have sold me an entire wiring harness, but wouldn't have taken two weeks to figure it out

I have seen that a couple times. The usual problem is that the pins didn't get seated fully when the harness was made. When first built they connect but a few years of hot/cold cycles and rough roads and they become intermittent. It's a PIA to find, because as you discovered with yours. Nothing looks like it's messed up in the block. I have also seen more than one where the fuse connectors LOOK fine but they no longer pass current. Pull the fuse block and they still look OK until you actually test the clips.

I'm just happy it happened in front of my house, and not where we camp in the Sierra Nevadas, 10 miles from the nearest paved road