The service manual will have the most correct full diagram.
This a work in progress showing the main power circuits.
There are two accessory circuits.
Q2 is only on when the key is in On or Accessory positions
Q3 is hot all the time.
So the fuse box is divided:
It has two fuses that are only hot when the key is turned to Run or Accessory.
It has two other fuses that are hot all the time.
A blank fuse location for options (A/C, tach, rear heater, etc)
Finally a 2 or 3 amp fuse for the instrument lighting circuit.
When I tried several accessories wipers, dash & dome lights, etc. they were not working.
Wipers are on a branch of Q2. No fuse in the box. Probably a breaker in the wiper switch. But if the key is not on, the wipers won't work.
Dome lights are fused. Power goes from the fuse box to the dome lamp, then switches are in the return wire. Any one switch will complete the circuit to ground.
Dash lights are special. They are fused twice. One in the feed to the headlight switch, and again between the headlight switch and the instrument panel.
Note the ammeter location in the circuit. It will indcate whether current is flowing out of the battery or into it.
It can sometimes help in trouble shooting.
It also can serve as a warning for major problems.
Over half way discharging shows a short circuit, or some thing(s) are drawing lots of power.
Over halfway charging can indicate battery was very low and continuous heavy charging can cause damage the battery or wires.
Discharging when the engine is running indicates the alternator is not suppying power (instead the battery is).
