92 GMC Sierra No power to fuel pump fuse.

The truck was working fine. Drove it to work. Left to go home, it wouldn't start. Changed fuel pump, filter, relay and oil pressure switch. Further troubleshooting revealed no power at fuel pump fuse.
Where does this fuse get its power? The Haynes manual is vague and shows an orange wire going to it. There are 2 gray wires. Any help will be greatly appreciated. Thanks.

Welcome to AF, check the wiring diagrams at autozone.com, repair guides. Look under chassis electrical.

Thanks. I went to Autozone.com. Unfortunately they do not list a repair guide for a 92 GMC or Chevy.

here is one thing you can do!. run a wire from a power source to the fuse (power side), and see if the pump kicks in.

Look here for diagrams:
http://www.autozone.com/az/cds/en_us/0900823d/80/08/79/51/0900823d80087951/repairInfoPages.htm

Sometimes you need to look up parts: For instance I looked up fuel pump for 92 GMC and found the online manual.

Hope this helps